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The DUI Process and DUI Defense in Arizona

Being stopped for a DUI in Arizona can be a scary experience. Being arrested and charged can be even more traumatizing, especially when you dont understand the criminal system or the DUI defenses available to you.

This page explains the criminal process from the initial traffic stop through to the sentencing, including explanations of common defenses to a drunk driving charge. Click on any of the links below to learn more.

If you or a loved one has been stopped or charged with drunk driving in the Phoenix or Tucson Arizona, please contact the DUI defense attorneys with Arentz Law Group PLLC. Schedule a free consultation to discuss your experience and your case.

Arizona DUI Traffic Stop

A DUI arrest begins with the traffic stop. Generally, most evidence against a defendant is gathered at during the traffic stop. The Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC recommend that people educate themselves as to their rights before a stop occurs. We also recommend that if you are stopped, you exercise your right to remain silent and contact a DUI defense attorney as soon as possible.

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Retaining DUI Defense Attorneys

A defendant may retain a DUI defense attorney at any time after arrest, whether it is immediately after the stop or the night before the court date. The Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC recommend that you contact us at least a few days before the court date.

DUI defendants have the right to an attorney or will be appointed one (a Public Defender) if they can not afford one. However, DUI defendants may be responsible for paying the costs of the Public Defender if it is later determined that he/she had enough money to pay for an attorney. Shortly after arrest is the best time to hire DUI defense attorneys to take control and defend the case.

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An arrest can occur for either a felony or a misdemeanor crime. For a felony crime, police must have "probable cause" to make an arrest, which may be conceptualized as a "good reason" to arrest. If the crime is a misdemeanor, an arrest can be made if the arresting person has a warrant or if the crime occurred in the presence of the arresting person.

It is important for a defendant to remember what the arresting officer did and said during the course of the arrest. Police do not have to read Miranda rights to a defendant after an arrest. However, failure to do so may be grounds to suppress certain statements or confessions. DUI defense attorneys can often use the arresting officers conduct or lack thereof to the defendants advantage.

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After an arrest, the defendant will be booked and then released. Generally, a defendant will not go to jail after a DUI arrest. When a suspect is booked the following occurs:

  • The defendant is taken to the law enforcement station.
  • The defendant is asked a series of routine questions.
  • The defendant is lawfully searched with or without consent.
  • The defendant is fingerprinted and photographed.

If someone you know is arrested, you can acquire booking information. You can do this by calling the jail or prison hotline for booking information. You will need the inmate's booking number or his/her date of birth and full name. The jail or prison will release information on the charges, the court date, the arresting agency and the bail amount.

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Post-Arrest Investigations

Post-arrest investigations may be done after the DUI arrest but before charges have been filed by the prosecutor. In DUI cases, a post-arrest investigation is often done if the prosecutor is deciding between filing a felony Aggravated DUI charge or a misdemeanor DUI. A defendant in this situation are sometimes told his/her case is "scratched" while the prosecutor decides which type of case to file.

A scratched case does not mean the case is dismissed or that it has gone away. However, "scratched case" is an indication that the defendant should hire our defense attorneys or another attorney immediately.

The Tucson and Phoenix area DUI defense attorneys with Arentz Law Group PLLC are aggressive and proactive. Involving them in the case before charges are filed allow the attorneys to contact law enforcement and the prosecutor and attempt to influence the charging decision to the defendants favor.

In Aggravated DUI cases, police officers investigate the M.V.D. record to make sure the defendant is the same person as the person with the prior DUI convictions, or to confirm the defendants M.V.D. status. Police officers might obtain records from other courts to prove a prior DUI conviction. Investigating officers also might research a suspect's driving history or prior convictions in other states. It is not required that the arresting agency release the police report before the defendant goes to court. However, sometimes the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC can talk the police into releasing the report.

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Decision to Charge

Both the County Attorney and the City Attorney have the authority to file felony and misdemeanor charges against a DUI suspect if they believe there is sufficient evidence for conviction. However, a City Attorney may only pursue to resolution misdemeanor charges. The City Attorney must hand over felony cases to the County Attorney.

For misdemeanor DUI cases, the police officer can cite the defendant directly into city or justice court. The officers decision to charge is often "rubber-stamped" by the court or prosecutor.

The Tucson area and Phoenix DUI defense attorneys with Arentz Law Group PLLC can represent you regardless of whether youre charged with a felony or misdemeanor and in any Arizona court you are required to appear in.

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First Appearance

On misdemeanor cases, the defendant can often avoid appearing for the first court date by hiring experienced DUI defense attorneys. However, felony cases always require the defendant to personally appear even if he/she hired DUI defense attorneys. If the defendant does not have DUI defense attorneys, the court will advise the defendant of his/her right to appointed counsel, and of his/her other basic rights.

At the initial appearance, the defendant will be read his/her rights and the charges against him/her. Bail or an appearance bond is sometimes required on serious cases or Aggravated DUI cases during the initial appearance. Bail is an "insurance policy" that ensures the defendant will appear before the court again. The amount of bail is determined by the seriousness of the offense and by the Judge. Bail can be $0 if the person is released "on their own recognizance (O.R.)", but it can be increased if the Judge feels that the defendant will not appear in court again. If the person fails to appear before the court, a warrant will be issued for his/her arrest.

During a later proceeding in front of the court, DUI defense attorneys can bring a motion to reduce bail. The judge decides whether to reduce bail and will consider the defendant's risk of flight and danger to the public. In a felony case, if the DUI defense attorneys ask for an O.R. release, the court will most likely set the matter for another hearing and order a pre-trial services report on the defendant. This process usually takes a week.

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Preliminary Hearing

Preliminary hearings only occur in felony Aggravated DUI cases that are not started by a grand jury indictment. In Arizona, a preliminary hearing is necessary (unless there is an indictment) and here the Judge determines whether or not there is sufficient evidence or probable cause to support the charges against a defendant and bind the case over to Superior Court for trial. During a preliminary hearing, the District Attorney or the Judge can add additional charges and order the defendant back into custody even if they are already out on bail.

If you have been charged with felony Aggravated DUI, do not take chances with your freedom. Contact the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC to discuss your case at no cost to you.

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Arraignment on the Information or Indictment

In Aggravated DUI cases, the defendant is taken before the Superior Court and informed of the charges. At that time, the defendant will answer to the charges by pleading not guilty or guilty. At the Superior Court arraignment, the amount of bail may be reviewed if a written motion is filed in advance of the hearing. If bail is reviewed, the amount may be increased or decreased at the court' discretion.

Discovery is usually given to the DUI defense attorneys after arraignment. Discovery includes but is not limited to police reports, medical records, probation reports, photographs, diagrams and viewing of physical evidence.

Discovery in DUI cases must be reciprocal, which means that the prosecution must provide the defense with the evidence they are using in the case. Neither the prosecution nor the defense may "hide" evidence and later introduce it during the trial.

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Pre-Trial Conference

At the pre-trial conference, DUI defense attorneys negotiate with the prosecuting attorney in order to obtain the best possible "deal" or plea for the defendant. The State is not required to offer a plea deal, but if one is offered, the DUI defense attorneys are required to discuss the deal with the defendant. It is then solely the defendants choice to accept or reject the plea.

A "deal" might include:

  • The prosecution charges the defendant with a lesser charge.
  • The prosecution agrees to a lesser punishment for the same charge.
  • The number of counts charged may be dropped.
  • Alternative sentencing may be imposed.

DUI defense attorneys may also file Pre-Trial Motions, which may assist in dismissing charges or changing the prosecution's position.

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The trial itself will normally proceed in the following order:

First, a jury will be selected. To do this, the judge, the prosecutor, and the Phoenix and Tucson area DUI defense attorneys from Arentz Law Group PLLC will ask the prospective jurors a series of questions designed to reveal strong biases, either for or against either side. After those people with strong biases have been removed from the jury panel, the prosecutor and your DUI defense attorneys will have the right to remove any two persons from the remaining panel. Thereafter, the judge will impanel a seven person jury to hear the criminal charges. At the conclusion of the presentation of the evidence only six jurors will deliberate on the charges. The seventh juror will be designated as an alternate and excused from the case.

Second, the prosecutor and then the defendants DUI defense attorneys will present opening statements to the jury outlining each sides theory of the case and what they feel the evidence will show.

Next, the prosecutor must introduce evidence in support of the charges made in the complaints against the defendant. The evidence will consist of testimony from witnesses and possibly presentation of exhibits. For each witness, first the prosecutor will question the witness and then the DUI defense attorneys will cross-examine that witness.

Then, after the prosecution has concluded the presentation of its case (or "rested"), the defendants DUI defense attorneys may or may not present evidence in defense of the defendant. If witnesses testify on behalf of the defendant, the DUI defense attorneys will first examine the witness and then the prosecutor will cross-examine the witness. The defendant may testify, but is not required to. In fact, the defendant is under no obligation whatsoever to either testify or produce any witnesses to testify on his/her behalf.

Whether or not a defendant testifies or puts forth any evidence at all is a strategic decision made between the defendant and the defendants DUI defense attorneys. The law does not require the defendant to testify or to produce any evidence. If the defendant chooses not produce evidence, the judge may instruct the jury that the jury may not take the fact that the defendant did not testify and/or produce any evidence into consideration when they deliberate on the charges.

After the conclusion of the defendants presentation of the case, the prosecutor will have a limited opportunity to present additional evidence to rebut any evidence presented by the DUI defense attorneys.

Once all evidence has been presented, the prosecutor and the DUI defense attorneys will make their closing arguments. Thereafter, the jury will deliberate and issue its decision.

If there are civil charges, such as 28 A.R.S. 701 (speeding), those charges will be decided by the judge and not the jury. After the jury returns its verdict on the DUI charge, the judge will issue his or her decision on the civil charges.

After the verdicts have been returned by the jury and the judge, the judge will proceed with sentencing on any charges for which the verdicts were guilty or responsible.

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M.V.D. Hearing

If you receive an M.V.D. Hearing notice, please contact the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC immediately to schedule a consultation. There are important deadlines involved with an M.V.D. Hearing and missing the deadlines can have a detrimental effect on your right to drive in Arizona.

An M.V.D. Hearing is a separate process that has nothing to do with the criminal case. M.V.D. suspensions and hearings vary depending on the defendants actions and M.V.D. history. Generally, a defendant has the right to an M.V.D. hearing on most new suspensions but is often required to request the hearing within fifteen days. If the defendant fails to request a hearing in time, the defendant could lose his/her right to the hearing.

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Sentencing is usually held immediately after a verdict in the DUI case is reached, but sentencing can occur as much as thirty days later. A sentencing hearing is a court hearing where the judge determines punishment. Punishment can include jail, prison, informal (unsupervised) probation, formal (supervised by a probation officer) probation, or some combination of the four.

A defendant may be sentenced to probation in addition to jail or prison for DUI. However, the defendant may be ordered to do some local custody time as a term of his or her probation. If the defendant violates his/her probation, the defendant may be incarcerated.

If probation is not granted, there is usually a range of three prison terms in each felony crime: the mitigated term, presumptive term, and aggravated term. The Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC argue against the prosecutor regarding the proper term based on the facts of the particular case. The final word is usually within the judge's discretion unless the plea agreement specifically outlines the agreed upon term.

Some alternatives to jail that might be negotiated by our Tucson area DUI defense attorneys are:

  • Treatment or Detox Programs
  • Electronic Home Monitoring
  • Residential Treatment Centers
  • Counseling
  • Weekend Work Programs
  • Community Service

Please contact the office of Arentz Law Group PLLC for a free consultation or if you have any other questions regarding the process of a DUI case. The Phoenix and Tucson area DUI defense attorneys with Arentz Law Group PLLC can help you with your case, but only if you contact them. Do not risk your freedom. Schedule a free consultation today.

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Common DUI Defenses

Please don't plead guilty to DUI without first consulting with an experienced Phoenix and Tucson area DUI defense attorney. The successful defense of a DUI case often requires not only experience but also the use of many defenses.

Preparation is critical and this includes a review of all potential DUI defense arguments available. In Tucson, Phoenix, and all of Arizona, there are numerous potential defenses to DUI cases and the DUI defense attorneys at Arentz Law Group PLLC believe an aggressive defense is useful to their clients.

Part of an aggressive DUI defense is a thorough pre-trial investigation that includes not only a review of available DUI defenses but also interviews of potential defense witnesses and interviews with the state's witnesses. The government begins with many advantages. Why not even the field or tilt it your way by retaining a highly experienced Phoenix and Tucson area DUI defense attorney? Contact the Arentz Law Group PLLC to schedule a free consultation.

Please select from the following common defense topics below:

ADAMS Issue and Defense in DUI Cases

In Arizona, most alcohol breath testing is done on a device known as the Intoxilyzer 5000. This device is limited in its accuracy. Before the State may use the breath test results in court or in motor vehicle proceedings, it must show that the device was at least capable of measuring within an acceptable range of accuracy when the person was arrested. If the devise was not testing within the acceptable range of accuracy when an arrested person was tested, then the State may not be able to use the test results against the defendant.

The state is also required to give to the arrested person's DUI defense attorneys all records of when the device's accuracy was tested. In 1999, it was discovered that many police agencies, including the Department of Public Safety and the Phoenix Police Department, were engaging in a systematic practice of not disclosing all accuracy test results and thus creating a false impression that the devices were working accurately when they were not. This practice had the effect of convincing arrested people that they had no basis to challenge the accuracy of the breath test results, when in reality they did have such a basis.

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The Retrograde Defense or B.A.C. at Time of Driving Defense

The subtractive retrograde is a method to estimate your true breath alcohol level at the time of driving. Generally, the human body requires between 45 minutes to two hours for all the alcohol that you consumed to enter your blood stream. For this reason, a person's blood alcohol concentration ("B.A.C.") may continue to rise after the traffic stop and show a much higher level during the later breath or blood test than existed when the person was operating the motor vehicle. When the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC do a retrograde defense, the total number of drinks in a defendant's system at the time of the breath or blood test is "related back" to the time of driving by subtracting the drinks consumed shortly before the traffic stop.

For example, assume a 180-pound man consumed two beers within an hour of his being pulled over by the police, and approximately one hour later, the suspect submits to a breath test, which indicates a B.A.C. of 0.12%. Between the time of the traffic stop and the time of the breath test, the suspect's B.A.C. continued to rise as his body physiologically continued to absorb alcohol. Under the retrograde, although the breath test accurately reported a 0.12% B.A.C., the defendant's actual B.A.C. at the time of driving will be retrograded or "reduced" to a 0.08% B.A.C. or below.

The Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC can retain expert witnesses to testify as to your estimated B.A.C. at the actual time of driving. Because an estimate is all anyone will ever be able to obtain, we may never know for sure whether or not any one defendant was over the legal B.A.C. limit at the time of the stop. However, there are some presumptions.

Under Arizona law, the following presumptions apply for the court and jury to consider:

  • If there was at the time of alcohol testing 0.05% or less alcohol concentration in the defendant's breath or blood, then it may be presumed that the defendant was not under the influence of intoxicating liquor;
  • If there was, at the time of alcohol testing, in excess of 0.05% but less than 0.10% (0.08% after August 31, 2001) alcohol concentration in the defendant's breath or blood, then no presumption arises, but that fact may be considered with other evidence in determining the defendant's guilt or innocence; and
  • If there was at the time of alcohol testing 0.10% (0.08% after August 31, 2001) or more alcohol concentration in the defendant's breath or blood, then it may be presumed that the defendant was under the influence of intoxicating liquor.

LEGAL UPDATE: With respect to the A(2) DUI charge, the Arizona legislature repealed the Rising B.A.C. Defense on July 18, 2000. However, the defense may be available now on A2 charges under the Desmond case. This defense still applies to the A(1) DUI charge and may be used by a Tucson area and Phoenix DUI defense attorney at trial.

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Constitutional Challenges to the A2 Charge

Although the State re-pleaded the "affirmative defense" on July 14, 2000, the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC believe that without this important portion of the overall DUI statutes, A.R.S. 1382(A)(2) is unconstitutional. This constitutional challenge has been raised successfully in other states and will possibly lead to the reinstatement of the affirmative defense under A.R.S. 1382(B).

"In considering an attack upon the constitutionality of the predecessor to A.R.S. 28-1382(A)(2) this court held that a statute is not void for vagueness if it meets two criteria. First, the statute must define the criminal offense with sufficient particularity that ordinary persons can understand what the statue prohibits. (citation omitted). Second, the statute must NOT encourage arbitrary enforcement."

"Defendant argues that, under the statute's language, a "person could be guilty of violation of A.R.S. section 28-1382(A)(2) by consuming alcoholic beverages after driving or by driving several hours after consuming alcohol when his blood level is considerably less than 0.10% and he is no longer affected by it." For these reasons, defendant argues, a person of ordinary intelligence cannot determine what conduct the statute prescribes. This argument is without merit. First, if one drives "several hours after consuming alcohol when his blood alcohol level is considerably less than 0.10%," that person does not violate 28-1382(A)(2).

Second, if one consumes alcoholic beverages within two hours after driving, with a B.A.C. of 0.10% or more within the two-hour period but not at the time of driving, that fact may establish an affirmative defense under A.R.S. 28-1382(B). Thus, reading the statute as a whole, as we have a duty to do, we conclude that the conduct made criminal by the statute is described with sufficient particularity for a person of ordinary intelligence." State v. Martin, 174 Ariz. 118, 847 P.2d 619 (1993).

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Inaccuracy of the Breath Testing Device

There are experts who believe the Intoxilyzer 5000 is a piece of junk. Others believe it is somewhat accurate within its own stated limits. In Arizona, the Arizona Department of Health Services (DHS) has enacted rules for the proper administration of breath testing and the maintenance of breath testing devices. Accordingly, for the test to be valid, the DHS testing procedure must be followed and the device must be calibrated to within a 10% accuracy range every 31 days.

In addition, the Department must evaluate each machine every 90 days using a seven-(7) test Standard Quality Assurance Procedure (SQAP). As a result, if any of the maintenance checks appear out of tolerance, then all breath tests administered during the time interval between the two maintenance checks may be inadmissible if challenged by the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC or any other attorney.

Portable or Preliminary Breath Testing Devices ("PBTs") are not admissible in jury trials but are often used by several valley police agencies. A "Preliminary breath test" usually refers to a hand-held breath-testing instrument used at the scene and prior to an arrest for the purpose of obtaining a determination of alcohol concentration from a specimen of breath. These devices are presumed to be less accurate than the non-portable devices.

The police often use a portable breath-testing device to measure the quantity of alcohol in a person's breath prior to arrest. The results of the portable unit are not accepted as "evidence" in court because of the device's scientific unreliability. Therefore, the digital results of the PBT are only useful to the police to help them determine whether or not to arrest the person being investigated. While you are not required by law to blow into a PBT, you should be careful to make sure what type of device the officer is asking you to use. You are only required to blow into the non-portable Intoxilyzer machines.

The Intoxilyzer 5000 is a breath-testing device manufactured by C.M.I., Inc., which the Arizona Department of Health Services has approved and designated for use in Arizona. This is the device that was used by the State that led to the ADAMS issue explained above. This machine analyzes the DUI suspect's breath sample without destroying it through a process of infrared spectroscopy, thus determining the amount of ethyl alcohol present in the breath sample.

Although the device has the potential for accuracy and reliability, the Tucson area DUI defense attorneys at Arentz Law Group PLLC believe it rarely lives up to that possibility. Design flaws combined with rules governing its use and maintenance by Arizona law enforcement officers make the Intoxilyzer 5000 prone to inaccuracy and unreliability. Consequently, there are many ways for their Phoenix and Tucson area DUI defense attorneys to challenge the prosecution's breath evidence in your drunk driving case.

Inherent Margin of Error

One method to challenge the accuracy of the Intoxilyzer 5000 is for the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC to comment on its inherent margin of error. The Intoxilyzer 5000 has an acknowledged plus or minus 10% margin of error. Thus, even when the device is calibrated and the administering officer determines it is operating properly, the Intoxilyzer 5000 will have a 20% range of error. This is a large range and it could mean your breath alcohol was really under the legal limit.

Radio Frequency Error

Another way to challenge the Intoxilyzer is for a Tucson area DUI defense attorney to comment on the power source and radio frequency interference. According to studies, the stability of the Intoxilyzer 5000's power source and its proximity to other devices emitting radio waves may cast doubt on its accuracy. This is important because police stations often have a huge variety of electronic equipment that cause radio waves.

Mouth Alcohol Error

A personal favorite of many Phoenix and Tucson area DUI defense attorneys is the Mouth Alcohol Defense. The Intoxilyzer 5000 is frequently incapable of distinguishing between alcohol in a person's mouth and blood alcohol. If you have been drinking alcohol, some may be trapped in your mouth, under your tongue or around your teeth.

Other contaminants in a person's mouth, such as, smokeless tobacco, denture adhesives, mints, and lip balm may also result in erroneous breath alcohol readings. Even an extremely small amount of mouth alcohol can lead to a huge increase in a B.A.C. reading.

Operator Error

Finally, operator error can be a problem raised by a Phoenix and Tucson area DUI defense attorney, since some law enforcement officers lack the proper training in the use of the Intoxilyzer 5000. Officers generally receive minimal training in the use of the device and are not provided with adequate written materials. As a result, a deep inquiry by our DUI defense attorneys into the officer's knowledge on the Intoxilyzer 5000 may be helpful to your case.

Physical Problems

A Phoenix and Tucson area DUI defense attorney can sometimes argue that a person's physical condition, or exposure to certain substances, affected the accuracy of the Intoxilyzer 5000. For example, a person suffering from diabetes, esophageal hernia, heartburn, liver disease, or other illnesses may get inaccurate results on the Intoxilyzer 5000.

Average Person Problem

The accuracy of the Intoxilyzer 5000 depends on the validity of several scientific assumptions about the average person. Is there really an average person? A Phoenix and Tucson area DUI defense attorney from Arentz Law Group PLLC can often argue successfully against this belief.

For example, with respect to body temperature, the Intoxilyzer 5000 assumes that every test subject has a core body temperature of 37 degrees Celsius and an expired breath temperature of 34 degrees Celsius. Based on this fallacy, the DUI suspect's breath reading will be 6.8% higher for each degree above the average than the suspect's actual breath reading. Our DUI defense attorneys can often use this discrepancy to our clients advantage.

The Circadian Rhythm, which refers to the "body's internal clock," further dispels the average person myth. The human body undergoes periodic daily physiological changes, involving, body temperature, sleep, hormonal levels, mineral concentrations, physical coordination, etc. For instance, studies show that morning consumption of alcohol resulted in higher peak concentrations than evening consumption of alcohol. Thus, the time of day when an alcoholic beverage is consumed may affect the rate at which the DUI suspect's body absorbs alcohol.

Another scientific assumption regarding the average person that a Phoenix and Tucson area DUI defense attorney often argues in drunk driving cases is that underlies the Intoxilyzer 5000's accuracy is the partition ratio. The partition ratio is a model of how much alcohol leaves the blood and enters the breath. The partition ratio assumes that the ratio between alcohol in the blood and alcohol in the breath is 2100:1. In other words, the Intoxilyzer 5000 assumes the alcohol concentration in the exhaled breath is 1/2100th of the blood-alcohol concentration. Yet, the actual ratio at which alcohol converts from blood to breath can range from 1300:1 to 3000:1. Thus, a DUI suspect with a blood-to-breath ratio of 1500:1 and a true B.A.C. of 0.08% would register a .112% BAC reading on an "accurate" Intoxilyzer 5000.

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Improperly Administered Field Sobriety Tests

The Phoenix and Tucson area DUI defense attorneys with Arentz Law Group PLLC believe that people who educate themselves about Field Sobriety Tests have a better chance of passing these tests if they are pulled over for drunk driving. The National Highway Traffic Safety Administration (NHTSA) has established guidelines regarding the administration of Field Sobriety Tests. The tests should not be given if the accused (a) is 50 pounds or more overweight; (b) is 60 years of age or older; (c) has any back, hip, leg, knee, or ankle injuries; (d) has any disability effecting balance or (e) is wearing shoes with heels two inches or higher.

Police officers in Arizona usually ignore these guidelines and give the tests to almost everyone. Then, presumably, they are ready to testify of poor performance. The Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC believe these tests are unfair and very difficult to perform even for those who are completely sober.

There are six standardized Field Sobriety Tests. The Phoenix and Tucson area DUI defense attorneys from Arentz Law Group PLLC recommend that you politely decline to take part in any of them. The six tests are:

(1) Horizontal Gaze Nystagmus Test ("HGN"): HGN is an eye test where the observer looks for "nystagmus" or an involuntary jerking of the eyes. The test measures the eyes' ability to follow a moving object in a horizontal and sometimes vertical plane. Although this phenomenon is frequently caused by the consumption of alcohol and/or certain drugs, nystagmus appears naturally in some people and may also be caused by the ingestion of certain antihistamines and other over-the-counter medications.

To properly administer the test, the officer must hold the stimulus, often a pen, 12 - 15 inches in front of the suspect's face and keep the tip of the stimulus slightly above the suspect's eyes. The officer must then move the stimulus smoothly and simultaneously check for clues in the order of lack of smooth pursuit, distinct nystagmus at maximum deviation and onset of nystagmus prior to 45 degrees. The officer must check for each clue at least twice in each eye. Consequently, the administering officer looks for three clues of neurological dysfunction in each eye for a total of six clues of impairment.

The Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC recommend that clients decline to participate in HGN eye tests. Gaze nystagmus may also be caused by many other things other than alcohol consumption such as drugs such as aspirin, caffeine and nicotine. Physical problems such as eye disorders, nausea, dizziness, influenza, measles, and neurological disorders can cause a person to fail the HGN eye test. Failure can also be cause by external conditions including temperature, rain, wind, sun, pollution, and headlights from other traffic on the road. There may be other undiscovered flaws associated with the HGN eye test.

When someone takes and fails the HGN eye test, a Phoenix and Tucson area DUI defense attorney can often argue that the officer incorrectly performed the test and request the court to take judicial notice on the proper procedures. A DUI defense attorney may also argue that no record of the test exists with which to gauge the officer's observations, the officer had inadequate training and experience in administering the test and/or that the officer did not have a protractor or other measuring device to measure the angle at which nystagmus occurred.

(2) Walk And Turn Test: The walk and turn test is another test that the Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC recommend you decline. This is a divided attention test intended to test your ability to follow instructions while standing heel to toe during the instruction phase and to walk a line heel to toe, for nine steps, turn around in small steps to your left, and return by taking nine heel to toe steps back. If you (1) start before the instructions are finished and lose your balance while listening to the instructions; (2) stop while walking to steady yourself; (3) miss heel to toe; (4) step off the line; (5) use your arms to balance; or (6) walk the incorrect number of steps, these actions are considered mistakes and will count against you.

(3) One Leg Stand Test: The one leg stand test is designed to test a person's ability to balance on one foot, while raising the other 6 inches off of the ground, and count by tens from 1001 to 1030. The administering officer will consider the following clues as signs of impairment: (1) sway back-to-front or side-to-side while balancing; (2) use your arms to balance; (3) hop; (4) put your foot down or (5) count incorrectly. A Phoenix and Tucson area DUI defense attorney will tell you that the secret to this test (that the officer will not tell you) is to place your weight on the back half of the foot you are standing on. Try this and you will find it much easier.

(4) Rhomberg Modified Test: In this test, the suspect stands with his/her feet together and arms at the sides, and then leans his/her head back with the eyes closed. Then, officers will record your actions and assume any slight balance problem is a sign of intoxication, regardless of the fact that many sober people will lose their equilibrium when performing this unnatural action. A Phoenix and Tucson area DUI defense attorney will recommend that you politely decline to take part in this test if asked to by the officer.

(5) Finger to Nose Test: In this test, the officer will tell you to stand with your feet together and arms down at your side. The officer will then tell you to close your eyes, tilt your head back, and then, using the finger instructed, tell you to touch the tip of your nose to the tip of your finger.

If you try this sober sometime, you will see how difficult it is if strictly judged. You are penalized for opening your eyes, swaying, failing to keep feet together or using the wrong hand. Even asking again to repeat the instructions means you are drunk.

(6) Finger Count Test: This test is easy even after a few beers, if you practice. It is difficult while sober if you don't practice. During this test, the officer will instruct you to use either the right or left hand and count out loud while touching the proper finger to your thumb. You must count 1-2-3-4, 4-3-2-1. A Phoenix and Tucson area DUI defense attorney will recommend that you politely refuse to do this test if asked by the officer.

You have the right to refuse to do any of the field sobriety tests listed above. The Phoenix and Tucson area DUI defense attorneys at Arentz Law Group PLLC recommend that you do not attempt to do these tests. Under stressful conditions, few people can perform the tests correctly, even if they are completely sober. There is no penalty for your refusal to take part in Field Sobriety Tests, and you usually have nothing to gain by participating. Remember, if you have been drinking the police will attribute the poor performance to possible intoxication. If arrested after performing these field sobriety exercises, this evidence will be used to prosecute you. Some people tell us they feel they did well on the Field Sobriety Tests, but we almost never see a police officer that agrees.

For each of these standardized NHTSA tests, an experienced Phoenix and Tucson area DUI defense attorney will investigate the possibility of inaccurate or unfair testing and determine ways to address inadequacies of the administering officer's instructions, demonstration, administration and scoring. The DUI defense attorneys at Arentz Law Group PLLC may challenge the results of your Field Sobriety Tests in the following ways:

The Non-Objective Police Officer. An experienced Phoenix and Tucson area DUI defense attorney can establish that police officers have an interest in the outcome of the case and are capable of making mistakes. In almost all cases, the officer has only told half the story in his police report. This is confirmed during the pretrial interview where the officer admits he/she only recorded the signs or symptoms which he/she believed were indicative of impairment and did not write down any behavior consistent with non-intoxication, i.e., that the client did not fumble retrieving his/her license from his wallet, had no trouble getting out of his/her car or that he/she was able to converse intelligently without slurring words or stuttering.

By confirming that the officer only wrote down the things he/she thought the client did wrong, a DUI defense attorney can establish the officer was more interested in creating a limited record for the sole purpose of supporting his/her decision to arrest, rather than making a fair and accurate record of all the facts and events as they actually transpired.

The Nervous Client. At trial, the officer may testify the driver fumbled with his/her wallet, slurred his/her words and seemed nervous or confused. A Phoenix and Tucson area DUI defense attorney can often successfully argue that the stress induced by a roadside confrontation with the police is enough to cause even the most well-spoken individual to stutter and the most coordinated to fumble and falter. It is normal for people to be nervous when confronted as the subject of the police investigation. This is often compounded when officers use a forceful tone and demeanor with suspects in order to establish command over the roadside stop and subsequent investigation.

Unnatural Tasks. The prosecution will invariably seek to show the Field Sobriety Tests requested of the defendant were such that any sober individual could easily perform them. However, in many cases, officers request suspects perform roadside tests without first inquiring whether the suspect has any mental or physical disability or infirmity which would preclude or hinder him/her from successfully completing the tests. Even if the officer does inquire and the person indicates that he/she does have an infirmity, an officer rarely attempts to determine how that infirmity could affect a person's performance on the Field Sobriety Tests.

When this is the case, a Phoenix and Tucson area DUI defense attorney can often argue that the officer did not really care whether the Field Sobriety Tests would be fair or accurate indicators of alcohol impairment. Showing the jury the only thing the officer was interested in was unfairly gathering incriminating evidence is a good way to successfully challenge the officers credibility. The officer will likely be asked by the prosecutor to demonstrate the ease with which these tests are performed. However, on cross-examination, an experienced DUI defense attorney will often get the officer to admit that he repeatedly practices the tests every time he demonstrates and administers the tests to DUI suspects. In essence, practice makes perfect. Although the tests may be easily performed by the officer, this battery of tests is foreign to most drivers who are asked to perform them for the first time under extremely stressful circumstances.

Poor Instructions. A Phoenix and Tucson area DUI defense attorney can often show that the arresting officer decided a suspect has failed a particular Field Sobriety Test due to inadequate performance when in fact it was the failure of the officer to explicitly describe what he/she wanted the driver to do. For example, if the driver was merely told to tip his/her head back, hold his/her arms out to the side and touch his/her finger to his/her nose, the driver should not fail the test merely because he/she did not touch the tip of his/her finger to the tip of his/her nose. Under the officers instructions, if any portion of the drivers finger touched any part of his/her nose, the driver was just doing as he/she was told by the officer, and doing it well. If the officer states the subject swayed while performing the one leg stand or any Field Sobriety Test requiring balance, then the officer should be asked if he/she told the driver not to sway. When the officer says no, it will confirm that the driver was unfairly judged on criteria he/she was not told would be on the test.

Unfavorable Conditions. Perhaps it was a dark, cold and stormy night when the driver was required to perform Field Sobriety Tests on the roadside. Perhaps the road was steeply graded or the emergency lane was filled with loose gravel. Maybe the driver was asked to perform the one leg stand and walk and turn in 5-inch stiletto heels.

If the conditions under which the driver was administered these tests were poor, it may invalidate the test and/or offend the jury. Once it has been established that conditions for the Field Sobriety Tests administered were not ideal, a Phoenix and Tucson area DUI defense attorney will often ask the officer if he/she considered giving the driver the test battery in the dry, warm, level, and well lit conditions of the police station. This will show the jury the officer was holding all the cards and controlling the outcome by unfairly administering the tests under conditions which guaranteed failure.

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Lack of Driving or Actual Physical Control

In a DUI case, the burden of proof is on the State, not on the defendant or his/her DUI defense attorneys. The State must prove more than just intoxication. Under Arizona law, the State must establish the defendant was driving or in actual physical control of a vehicle while either impaired by alcohol or drug consumption, or with a blood-alcohol concentration of 0.08% (%0.10 for cases occurring prior to August 31, 2001) or more within two hours of driving.

To determine "actual physical control" the court looks at the "totality of circumstances". A Phoenix and Tucson area DUI defense attorney can often argue one or more of these factors when defending their clients. Factors that may be considered include but are not limited to the following: whether the vehicle was running or the ignition was on; whether the defendant was awake or asleep; whether the vehicle's headlights were on; where the vehicle was stopped (either on the road or legally parked); whether the defendant had voluntarily pulled off the road; the time of day and weather conditions; whether the heater or air conditioner was on; whether some or all of the windows were up or down, and any explanation of circumstances advanced by defendant. In some cases there may be no witnesses to testify who was driving a vehicle.

Therefore, the State may be unable to meet its burden of proving the accused was driving or was in actual physical control of the vehicle. A Phoenix and Tucson area DUI defense attorney can ask for a case dismissal, a directed verdict or a non-guilty verdict. Often the courts look to whether the defendant actually posed a threat to the public by the exercise of present or imminent control over the vehicle while impaired, rather than simply using the vehicle as a stationary shelter.

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Use of Expert Witness in Your DUI Case

To properly defend your case, it may be necessary for a Phoenix and Tucson area DUI defense attorney to obtain an expert witness on the forensic testing of blood and breath alcohol. An attorney will discuss the facts of your DUI case with you thoroughly so that they can determine whether or how our expert witness may help with your defense.

No Reasonable Suspicion to Stop

An investigatory stop is unconstitutional if the stop is not supported by reasonable suspicion that criminal activity is afoot. Thus, if the law enforcement officer lacked a constitutionally valid reason for making the traffic stop, all evidence of impaired driving obtained as a result of the unlawful stop must be suppressed. Common reasons for stops are other traffic violations. The lack of other violations could call questions to the reason for the stop. A Phoenix and Tucson area DUI defense attorney will thoroughly evaluate your case with you to determine if this a defense you can take advantage of.

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No Probable Cause to Arrest

Probable cause to arrest means reliable information within an officer's knowledge which would lead a reasonable person to conclude that criminal activity has been or is being committed. If objective facts and circumstances, indicative of impairment or intoxication, did not exist at the time of the arrest, the arrest is unconstitutional and a Phoenix and Tucson area DUI defense attorney may argue that the case should be dismissed. Once in a while, police officers will admit they did not observe the normal factors used to determine that a person is under the influence. This might lead to a challenge.

Many arrests result from "task forces" or sweeps where officers (often from several cities) team up to arrest as many people as possible so they can make the headlines in the newspapers. If this happens, the result may be traffic stops that lack probable cause.

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Denial of the Right to Counsel

If you become a drunk driving suspect, request to speak with a Phoenix and Tucson area DUI defense attorney as soon as possible. Under Arizona criminal law, when a DUI suspect requests a lawyer, the police must provide the defendant with an opportunity to speak with a lawyer telephonically as soon as is reasonably possible. Where the police unreasonably delay or deny the suspect's request to speak with an attorney, depending on the particular facts, the remedy in the criminal case is either dismissal or suppression of all the evidence obtained after the violation of his or her constitutional right to counsel. Thus, it is very important to demand to speak with your attorney as soon as you are stopped.

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Violation of Miranda Warnings

After a DUI suspect is taken into custody but prior to any questioning initiated by law enforcement officers, the officers must read the suspect the Miranda warnings; otherwise a Phoenix and Tucson area DUI defense attorney can argue that any statements made by the suspect should be inadmissible in court. The Miranda warnings state that the suspect:

  • has a right to remain silent;
  • any statement he or she does make may be used as evidence against him or her;
  • he or she has the right to the presence of an attorney; and
  • if he or she cannot afford an attorney, one will be appointed for him or her prior to any questioning.

Unless these warnings or a waiver of these rights are shown, any incriminating statements made during the custodial interrogation may be suppressed.

A Phoenix and Tucson area DUI defense attorney will recommend that you exercise your right to remain silent and do not answer questions such as where you were, what you were drinking, number of drinks, or when you last ate food.

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Denial of Independent Tests

Under the Fourteenth Amendment to the United States Constitution, the defendant has a due process right to collect independent scientific evidence of his or her blood alcohol concentration (BAC). A Phoenix and Tucson area DUI defense attorneys can often use the States actions against them if this request is denied. Independent chemical tests are exculpatory evidence, and the State may not unreasonably interfere with a defendant's reasonable efforts to gain such evidence. This means even if the State intends to book the defendant into jail, the defendant must be given the opportunity to immediately arrange for an independent blood test if the defendant requests such an opportunity.

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Problems in Blood Alcohol Testing

If any foundational deficiencies in the State's collection, storage or analysis of the chemical evidence exist, a Phoenix and Tucson area DUI defense attorney can argue that the results of blood alcohol test should be suppressed. Results of blood alcohol testing are only admissible as evidence against the defendant if the prosecution can establish the blood was drawn by qualified personnel and the particular scientific analysis utilized complied with scientific standards and State requirements as to calibration and maintenance.

In Arizona, the person who drew the blood must have been qualified by law to draw a DUI suspect's blood for blood alcohol concentration testing. A Phoenix and Tucson area DUI defense attorney may challenge the results of the blood alcohol testing if the person who drew the blood was not qualified by law to draw the blood.

A DUI defense attorney will often ask for the Blood Swab during discovery. The Blood Swab used to cleanse the site of venepuncture must be contaminant free. Hospitals frequently use isopropyl alcohol to clean the site of the blood draw. However, isopropyl alcohol can contaminate the blood sample. Also, if police used a NIK blood kit, due to a manufacture recall, the content of the forensic swab may be contaminated.

DUI defense attorneys often ask if the whole blood or just the plasma was tested. Whole blood is composed of cellular material, plasma and fibrinogen (clotting agent). In plasma draws, hospitals typically test serum or plasma for the presence of alcohol. Conversely, forensic blood draws test for the precise blood-alcohol concentration. Medical blood draws, therefore, present several problems for DUI suspects. First, when the hospital lab tech centrifuges the blood sample, the solid, cellular material (the whole blood) is removed, which leaves the same amount of ETOH in a smaller volume of liquid. Thus, hospital tests may artificially inflate the DUI suspect's alcohol concentration by as much as 20% to 30%.

DUI defense attorneys can also sometimes use hematocrit to their clients advantage. Hematocrit is the percentage of whole blood comprised of cellular material. For instance, a hematocrit of 47 means that 47% of the person's blood is composed of cellular material, and the remaining 53% is plasma (mostly water). The hematocrit for a male is 47% and for a female is slightly lower.

Hypothetically, if the DUI suspect had a hematocrit of 60 and the hospital tested plasma, what would result? The lab analysis will report a higher BAC for the DUI suspect, because he or she will have a lesser volume of liquid, and alcohol always gravitates toward the liquid. Thus, the higher the hematocrit the higher the DUI suspect's BAC. Typically, hospital records will show hematocrit.

If the drunk driving suspect was given an IV prior to having blood drawn, a Phoenix and Tucson area DUI defense attorney may be able to use this to the suspects advantage. Administering an IV to a DUI suspect prior to a blood draw artificially increases the person's blood-alcohol concentration. Because alcohol tends to follow water in the blood, intravenously administered liquid draws more alcohol out of body tissue, thereby, artificially increasing the DUI suspect's blood-alcohol concentration.

A Phoenix and Tucson area DUI defense attorney will often subpoena the blood test kit used on the drunk driving suspect. Blood test kits manufactured by NIK Public Safety, Inc., have expiration dates regarding the period that the vacuum in the vacutainer tube is warranted. Each tube contains a preservative and an anticoagulant. A precise vacuum exists in the vacutainer tube to assure a precise amount of blood will be drawn and mixed with these chemicals in a precise ratio. Thus, imprecision in the mix, i.e., too much chemical or not enough blood, can skew the test result.

Additionally, if the vacutainer leaks, airborne microorganisms may contaminate the sample. Combining blood with microorganisms results in fermentation. ETOH is a byproduct of fermentation, and there is no way to distinguish between alcohol consumed by a DUI suspect and alcohol created by fermentation.

Each vacutainer kit is intended to take 10 ml of blood. Each kit contains two chemicals: 100 mg of sodium fluoride (a preservative to prevent fermentation and neo-production of ETOH) and 20 mg of potassium oxalate (an anticoagulant designed to prevent clotting of the blood). The issue for DUI defense attorneys is whether these chemicals were in the vacutainer tubes because these chemicals are critical to an accurate test result.

NIK kits have two sets of instructions. One for the person drawing the blood and one for the police officer involved in the DUI situation. One of the instructions pertains to mixing of the blood immediately after the blood draw. After the blood is in the vacutainer, the person drawing the blood is to properly mix the blood and chemicals in tubes. The blood must then be tested for alcohol using only approved methods. These methods include gas chromatography and gas head space chromatography.

Gas Chromatography. There are two types of gas chromatography used in blood analysis: (1) direct measurement of the blood sample and (2) measurement of the gas in the headspace above the liquid. Gas Chromatography ("G/C") is a method of (1) identifying a substance and (2) determining the concentration of that substance. The process is both qualitative (what is it?) and quantitative (how much is there?).

Gas Head Space Chromatography. In gas chromatography you are actually testing the DUI suspect's blood. In gas head space chromatography, you are testing the gas or vapor above the liquid--not the liquid itself. The head space is the space above the liquid. The alcohol evaporates (at a rate of speed determined by temperature) from the liquid to the gas in the head space above the liquid. The alcohol will evaporate until it reaches the point of equilibrium. Equilibrium is determined by temperature. The higher the temperature, the more alcohol in the gas above the liquid.

When gas head space chromatography is used, a Phoenix and Tucson area DUI defense attorney can often argue that core body temperature variation and expired breath variation can artificially inflate a breath test reading. Breath testing is based on the relationship between alcohol in the blood and alcohol percolating from the blood into the vapor in the lungs. The assumption underlying breath testing is that whatever alcohol is present in one ml of breath, 2100 times that amount will be present in one ml of blood.

This same theory underlies gas headspace chromatography. With this process, the lab makes up the same mixture of the blood plus the internal standard. They heat the sample and draw off the vapor for analysis. Then the vapor is injected into the chromatograph. The process assumes there is a relationship between the alcohol in this vapor and the actual alcohol in the blood.

However, this assumption raises several questions that DUI defense attorneys can use to help their clients: How is the temperature regulated? What was the temperature? What is the relationship between the ETOH in the headspace and the ETOH in the blood? The primary disadvantage to headspace chromatography is the partition ratio and the effect of temperature and pressure.

Machine Error can also be a problem and is an issue often raised by DUI defense attorneys. Like the IR 5000, the G/C has a 10% margin of error under Arizona's DHS administrative regs. A 20% margin of error is not uncommon. The process is not that precise.

Gas Chromatography analysis rides on the validity of the standards that are used to calibrate the chromatograph. The integrity of the whole process is determined by the accuracy of those standards.

In the end, who really knows if the blood test they tested even came from your body?

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Motion to Suppress Breath Test

A Phoenix and Tucson area DUI defense attorney can file a motion to suppr

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