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Call Now: 480-775-4800

DUI (Felony)

Arizona Driving Under the Influence, Driving While Intoxicated Defense Lawyer, or DUI Attorney.

Arizona’s DUI laws have changed. Make sure you have an attorney that knows the current law and how each court is interpreting the new laws.

Shell & Nermyr attorneys annually attend conferences across Arizona and the country to stay current on all DUI defense law and the science behind defending people accused of DUI.

More and more people are being charged with DUI due to driving with prescription medication in their system. This type of DUI is a very special area in that often time’s doctors are required to testify in court to defend the DUI arrest. The government can charge a person with DUI if they state can prove that the drug in their system affected their ability to drive. Many medications have warnings against driving on the bottle but some do not. If a person has a valid prescription for the drug the state will be required to prove that the drug impaired the person’s ability to operate the vehicle. If a person does not have a valid prescription all the state has to prove is that the person is that a person was driving and they had a drug or its metabolite listed in A.R.S. §13-3401 in their system at the time of driving. If you are charged with DUI based on a prescription drug so not assume the state will dismiss the case simply because you have a prescription. Call the DUI attorneys at Shell & Nermyr and let the best criminal defense attorneys help you.

When you are facing charges of DUI, you need an experienced aggressive attorney to make sure your rights are protected. On this page, you will find general information about DUI defense. For information about how the lawyers at Shell & Nermyr PLLC can help you, contact us today at 602-745-1211.

Shell & Nermyr PLLC represents individuals arrested for driving under the influence (DUI) throughout the greater Phoenix Metro area, Maricopa County and throughout the entire state of Arizona. Contact us today. We can help. Many people do not realize that DUI is a criminal offense in Arizona. That is why it is important to hire the best criminal defense attorneys in Arizona to help you in your DUI case.

Overview of the Crime of DUI

Arizona has some of the toughest laws and severest penalties for driving under the influence. As we all know, it is illegal for a person to operate a motor vehicle after consuming too much alcohol and/or drugs to a degree that it impairs his or her ability to operate a motor vehicle. Both criminal and civil penalties for DUI are harsh and often include:

  • Jail or prison time
  • Loss, suspension, or revocationof license
  • Large fines
  • Substance-abuse treatment
  • Community service
  • Restitution
  • Criminal record
  • Ignition interlock devices
  • SR22 Insurance
  • Impounding the vehicle for 30 days

In addition, the increase in car insurance costs and affect on your career may have lifelong negative consequences.

Terminology and Elements of the Crime of DUI

The criminal offense of DUI goes by a variety of names, including:

  • Driving under the influence (DUI)
  • Driving while intoxicated (DWI)
  • Operating under the influence (OUI)
  • Operating while intoxicated (OWI)
  • Driving while under the influence (DWUI)
  • Driving with illegal Drugs in your system (DUI)
  • Actual Physical Control while under the influence (APC)

In the language of the various state statutes, a DUI conviction requires driving or operating a vehicle or motor vehicle. While that sounds straightforward, a review of DUI cases shows otherwise.

Driving Requirement

The requirement of driving or operating implies that the driver must have some sort of control or command of the vehicle. Guilt or innocence may hang on whether the defendant was actually “driving” in a particular circumstance. What if he or she was just sitting behind the wheel of a car but it was off? What if the defendant was sleeping there? What if the keys were in the defendant’s pocket and not in the ignition? What if that car was out of gas and could not be started? What if it was idling? What if it was being towed? Courts nationwide have considered various scenarios to determine whether the necessary control over the vehicle was present. In Arizona a person can be charged with and possibly convicted of DUI even if they had not driven and did not plan on driving after they consumed alcohol. Theoretically, in Arizona, a person can be charged with and even convicted of DUI if they were washing their car in their driveway and had the keys in the ignition to listen to music. This is an extreme example, but the laws in Arizona are extreme. The criminal defense attorneys at Shell & Nermyr have convinced the prosecution to dismiss many cases because they were able to show that their client was not in control of their vehicle. The DUI attorneys at Shell & Nermyr have convinced many courts to find their client not guilty of DUI because they were able to show that their client was not in control of their vehicle. Many people overlook the issue of “driving” and only focus on the impairment and alcohol concentration, but driving is one of the elements the state must prove beyond a reasonable doubt. In many cases driving is not a big issue because the person was pulled over by a police officer but in some cases it is the best issue in defending a DUI case.

Vehicle Requirement

Cars, trucks and vans are obviously considered to be vehicles for DUI law purposes. However, people have been convicted of DUI while operating motorboats, mopeds, dirt bikes, snowmobiles, electric wheelchairs, golf carts, bicycles and ATVs. A person can be charged with OUI for driving a boat or other watercraft.


One way prosecutors prove driver intoxication is through scientific testing of the amount of alcohol in the body, usually by analyzing the breath or blood of the driver. These tests are usually administered by machines, such as the Intoxilyzer. In Arizona, a person with a blood-alcohol concentration (BAC) over .08 is considered legally intoxicated. Most cities in the Phoenix area now draw blood from a driver rather than test their breath. Once blood is drawn, the crime lab will test the blood using a gas-chromatograph machine.

The cities in Arizona now drawing blood rather than testing breath are:

  • Phoenix (in most cases)
  • Mesa
  • Gilbert
  • Chandler
  • Scottsdale
  • Peoria
  • Surprise
  • Tucson
  • Arizona Department of Public Safety or DPS

The cities in Arizona that continue to test breath rather than blood are:

  • Tempe
  • El Mirage
  • Glendale
  • Maricopa County Sheriff (MCSO)
  • Tolleson
  • Fountain Hills
  • Arizona Department of Public Safety or DPS

The Implied-consent law creates the legal presumption that if a person takes advantage of the privilege of driving, he or she automatically consents to chemical testing to determine his or her BAC, but only if the police officer has probable cause to believe the person is driving under the influence. If a driver refuses to take a chemical-alcohol test, his or her drivers’ license may be suspended for an entire year. However, this suspension is not automatic. A person accused of refusing to provide a blood or breath sample can challenge the suspension. Contact the criminal defense attorneys at Shell & Nermyr to learn how to fight the suspension.

Blood & Breath Testing

Many people now believe that BAC (Blood Alcohol Concentration) test results over the legal limit are proof of intoxication. This is not true. Defendants can challenge the BAC results by showing irregularities in the test administration procedure or problems with the test equipment. Police officers make mistakes every day, criminalists make mistakes every day, and machines make mistakes all the time. For example, the DUI lawyers at Shell & Nermyr often advise retesting of your blood sample. Re-testing of the blood is low cost and it is done by a validated lab here in Arizona. The re-test results are just as admissible in court as the police’s test results. A good DUI attorney may be able to obtain dismissal of the case entirely by challenging and/or re-testing the BAC. Additionally, like all scientific testing there is a +/- margin of error. In DUI cases, the margin of error is +/-10%. Therefore, if a person’s blood or breath was tested to be a .087; our expert will testify that it could be as low as a .079 (which means, “NOT GUILTY”). However, the experts for the state argue that the margin of error is +/-5% therefore it is imperative that you hire the best DUI attorney you can to fight for you in court.

Field Sobriety Tests – Coordination Testing

You can refuse to do any field sobriety tests.

Other types of evidence used by prosecuting attorneys to show intoxication include drivers’ statements, witness and police observations of behavior and driving patterns and circumstantial evidence. Police also gather evidence by administering standard field sobriety tests (FSTs) at the scenes of traffic stops or at a DUI van, or at the police station. Police officers are very clever in convincing people to try to complete field sobriety tests. The most common way police go about it is to say “you look ok to me but I just want to make sure I’m right so would you please walk a line for me?” Unless a person is 100% sober nothing good can come from attempting the field sobriety tests. On the walk and turn test alone, there are over 90 things a person can do wrong and if a person makes three little mistakes the tests says you failed.

Common field sobriety tests include: (*validated by NHTSA)

  • Horizontal-gaze-nystagmus test (HGN)
  • Finger-to-nose test
  • One-legged stand
  • Walk-and-turn test*
  • Rhomberg Modified*
  • Counting backwards
  • Reciting the alphabet

Driving is the basis of the American lifestyle, permeating every activity we do. We rely on driving to get to work, to socialize, to run errands and to vacation. Licensed drivers transport children, people with disabilities and senior citizens to important appointments and activities. The country’s entire economy depends on people driving; from driving personal cars to truckers transporting goods across the country. A DUI conviction can bring a screeching halt to your life. If you face DUI charges, a criminal defense lawyer can fight for you and help protect your interests and those of your family and loved ones. But hiring the best criminal defense attorney is more important than just any hiring a DUI lawyer.

The attorneys at Shell & Nermyr PLLC are the best trial attorneys in the state of Arizona. Shell & Nermyr PLLC represents individuals arrested for driving under the influence (DUI) throughout the greater Phoenix Metro area, Maricopa County and throughout the entire state of Arizona. We can help.

The Prosecutor’s Role in a DUI Case

Prosecution refers to the government’s role in the criminal-justice system. When criminal activity is suspected, it is up to the government to investigate, arrest, charge and bring the alleged offender to trial. A prosecutor is a lawyer who works for the government. Prosecutors do not care that you need your driver’s license; prosecutors do not care that you will lose your job if you go to jail. Prosecutors want a conviction and they will ask a judge to limit your constitutional rights in order to secure the conviction. The attorneys at Shell & Nermyr PLLC have never been prosecutors. The criminal defense attorneys at Shell & Nermyr have never been on the same side as the police and have never asked a judge to limit your constitutional rights in order to secure the conviction. Prosecutors may be called county attorneys, city prosecutor’s, district attorneys or states’ attorneys. Some defense lawyers even brag that they are former prosecutors. There is absolutely no advantage to hiring a former prosecutor. Some jurisdictions may even have experienced police officers act as prosecutors in DUI cases. The prosecutor is the opponent or “adversary” of the criminal defendant and his or her attorney; the two sides go head-to-head against each other in court. Arguably the easiest job in the legal field is a DUI prosecutor. Generally the only eyewitness is an experienced police officer, almost every case involves scientific blood analysis, and the public (jury) often timers trusts the government, i.e. police officers and prosecutors. That is why it is so important to have a respected criminal defense attorney on your side. You need an attorney that the judges respect, the prosecutors fear, and the public (jury) trusts. The DUI and criminal defense attorneys at Shell & Nermyr have the reputation and respect from their adversary necessary to get the job done right.

The Impact of a DUI Conviction on Your Auto Insurance

An alcohol-related charge and subsequent DUI conviction can bring many negative consequences into your life, possibly including jail or prison time, a criminal record, car repair or replacement, restitution, guilt and grief over harm to others, higher insurance premiums, a civil lawsuit, fines, court and administrative fees, community service, alcohol education, substance-abuse treatment, social stigma, restrictions on or revocation of your driver’s license, restrictive probation, Ignition Interlock Device, and others. If you are arrested for or charged with DUI, a criminal defense lawyer can advise you about your legal rights and help you fight the charges. The criminal defense attorneys at Shell & Nermyr can be contacted by email at mark@arizonastriallawyers.com and chad@arizonastriallawyers.com.

Many of the DUI laws in Arizona changed in January 2012. Now judges have discretion to suspend a lot of the jail time originally ordered for a DUI conviction. The courts can suspend a significant amount of the jail time and the court can allow all but 20% of the sentence to be served on home detention rather than in jail. Given that the law is rather new some of the courts are interpreting it differently and some of the courts are not even suspending jail time upon installation of an ignition interlock device.

It is important to hire an attorney that knows how the individual courts and judges are interpreting the new law. For example: in the city of Phoenix alone some judges order that a person spend two days in jail for an extreme DUI (.15) and seven days on home detention. Other judges in the same building are requiring a person to spend six days in jail and three days on home detention. In Mesa for example, there is no suspending of jail time for installing an ignition interlock device. Therefore, for an extreme DUI (.15) a person is required to spend six days in jail and 24 days on home detention. These are significant differences in jail time and in costs associated with that jail time. A person facing a DUI needs to know up front what the consequences could be in case of conviction. Please take a look at the record of Shell & Nermyr. No other firm can compare to our record.

Not only is it important to hire an attorney that knows the individual courts and judges. It is important to hire an attorney that is respected by the courts, the prosecutors, and even the police. The attorneys at Shell & Nermyr have earned the respect of prosecutors, judges and police. We have earned that respect by working hard, being honest, and getting the results for our clients. Nothing is more important than your attorney’s reputation.

Many criminal defense attorneys brag that they at one time were prosecutors. Here at Shell & Nermyr none of the attorneys have ever been prosecutors. And we take pride in the fact that we have never been on the side of the government we have never trusted police officers and we have never asked a court to take away a person’s rights or incarcerate them. In order to be a prosecutor you have to trust police officers, you have to ask the court to limit citizen’s rights and then you ask the court to put a person in jail. Many of the defense attorneys that were formerly prosecutors simply changed sides so they could make more money. There is no advantage to hiring an attorney that was a prosecutor. Any good defense attorney knows how prosecutors think and how prosecutors build a case, what great defense attorneys know is how to break down that case.

The attorneys at Shell & Nermyr have been successfully defending people accused of crimes since 1999. We have earned the respect of our adversaries and the fear from police officers throughout the state of Arizona. When the court and prosecutors see that Shell & Nermyr are on the case they know they are in for a fight.

Frequently Asked Questions about DUI

Q: What is “blood-alcohol concentration” or “blood-alcohol level”?
A: Blood-alcohol concentration (BAC) is the level of alcohol in the bloodstream from drinking alcoholic beverages. BAC readings are used in court as evidence in DUI cases. The most common method of measure in Arizona is a blood test, although breath and/or urine testing is sometimes done. A result of .08 or higher may establish a presumption of intoxication. Just because the results are over .08 does not mean all is lost. Shell & Nermyr has obtained dismissals and not guilty verdicts in many cases where the BAC was over .08.

Q: Can I refuse a Breathalyzer test?
A: Short answer is “yes”. But in most cases it is not in your best interest to refuse. Arizona has an implied consent law providing that a driver impliedly consents to alcohol testing just by the act of driving. A refusal to take a breath test is itself a violation subject to stiff penalties. For example, refusing a breath test can result in automatic driver’s-license suspension. If you are ultimately found guilty of a DUI offense, there may be additional penalties because of the test refusal, such as a stiffer sentence. Your test refusal may also be used as evidence against you in a DUI case. For example, when the arresting police officer is testifying, he can state that when he asked for a breath or blood sample, the driver refused to give one.

Additionally, with the advent of facsimile machines, officers are able to get a court order from a judge to obtain the blood sample anyway. Therefore, almost every refusal is followed by a fax to a judge for a search warrant to get the blood. Then the person not only is facing the one year suspension but they are facing the DUI charge as well.

Q: Are breath-test results always accurate?
A: The United States Constitution and Arizona courts allow the defendant in a DUI case to challenge the scientific accuracy of breath tests and blood tests. Some of the more common challenges are: improperly calibrated equipment; the equipment was repaired recently; there are outside forces that affected the test results; or inadequately trained officers. If the test results are inadmissible or can be challenged, the case becomes much stronger for a driver. The state will probably be left with having to prove their case using other evidence, such as eyewitness testimony and field-sobriety test results, which is less reliable evidence.

Q: What if I lose my license but continue to drive?
A: If a person whose license has been revoked or suspended due to DUI chooses to drive without a valid license and is pulled over, he or she stands to suffer more serious consequences, including possible fines, jail, forfeiture of his or her vehicle and extension of the license revocation/suspension. The public transportation system in Arizona is very poor, it is next to impossible to be a productive member of society in Arizona without driving.

Q: How can I get to work if I cannot drive?
A: Many people are forced to rely on the city bus, or rides from friends, family members, or co-workers for transportation to and from work during periods of license suspension or revocation. In Arizona, a person may be granted a restricted license, allowing him or her to drive just to and from work, school, medical appointments, court, and alcohol counseling only. On a second DUI, Arizona requires an alcohol evaluation as part of the restricted license application. If a person with a school and work permit is caught driving outside of its limitations, further penalties may be imposed.

Q: How can I get automobile insurance after a DUI conviction?
A: Although your rates will likely be higher, your insurer may continue to insure you even after a conviction. A prior or subsequent clean driving record may result in lower rates in the future. If your insurer drops you as a result of the conviction, another insurance company may be willing to accept the risk. In fact, some companies specialize in offering nonstandard insurance to drivers who have been convicted of DUI, but the rates are much higher. Another possible source of insurance for high-risk drivers may be state insurance programs created for just these types of drivers; this is known as SR22 Insurance.

Q: What is the punishment for DUI or DWI?
A: The following are the mandatory minimum punishments in Arizona. Whether a judge hands down more than the minimum depends on which city the DUI occurred.

ARS 28-1381(A)(1) or (A)(2) First Offense .08:

  • 10 days in jail / 9 of which may be suspended upon counseling
  • Alcohol and or drug counseling
  • 12 Months of Ignition Interlock Device – May be reduced to 6 months if compliant
  • Diver License Suspension – 90 suspension with 60 day work permit
  • Fines & Assessments

ARS 28-1382 First Offense .15:

  • 30 days in jail / 21 of which may be suspended upon installation of ignition interlock for 1 year
  • In some courts the 9 days are served by 6 days in jail & 3 days on home detention
  • Alcohol and or drug counseling
  • 12 Months of Ignition Interlock Device
  • Diver License Suspension – 90 suspension with 60 day work permit
  • Fines & Assessments

ARS 28-1382 First Offense .20:

  • 45 days in jail / 31 of which may be suspended upon installation of ignition interlock for 1 year
  • In some courts the 14 days are served by 9 days in jail & 5 days on home detention
  • Alcohol and or drug counseling
  • 18 Months of Ignition Interlock Device
  • Diver License Suspension – 90 suspension with 60 day work permit
  • Fines & Assessments

ARS 28-1381(A)(1) or (A)(2) Second Offense .08:

  • 90 days in jail / 60 of which may be suspended upon counseling
  • In some courts the 18 days are served by 12 days in jail & 5 days on home detention
  • Alcohol and or drug counseling
  • 12 Months of Ignition Interlock Device
  • Diver License Revocation
  • Fines & Assessments
  • Community Service

ARS 28-1382 Second Offense .15:

  • 120 days in jail / 60 of which may be suspended upon counseling
  • Alcohol and or drug counseling
  • 18 Months of Ignition Interlock Device
  • Diver License Revocation
  • Fines & Assessments
  • Community Service

ARS 28-1382 Second Offense .20:

  • 180 days in jail / 90 of which may be suspended upon counseling
  • Alcohol and or drug counseling
  • 24 Months of Ignition Interlock Device
  • Diver License Revocation
  • Community Service
  • Fines & Assessments

Q: What is the best way to beat a DUI charge?
A: Retain the services of Shell & Nermyr, is the best way to avoid being convicted of DUI. For some people, even one drink can impair their driving abilities so it is important to know how much alcohol is too much alcohol. However, if you have been charged with driving under the influence, an experienced DUI defense lawyer can work to improve the outcome of your case. The attorneys at Shell & Nermyr PLLC are the best trial attorneys in the state of Arizona. Shell & Nermyr PLLC represents individuals arrested for driving under the influence (DUI) in Arizona and throughout the greater Phoenix Metro area and Maricopa County. Contact us today. We can help.

Q: If I simply intend to plead guilty, why do I need a lawyer?
A: At Shell & Nermyr we offer a unique payment plan for people that want to plead guilty but want the assistance of some of the best lawyers in Arizona. Nobody should plead guilty without having an experienced DUI lawyer look at the case first. It is surprising how often police officers make mistakes or the blood or breath testing machine is malfunctioning. It takes a trained legal eye to spot those legal DUI loopholes. The prosecutor and judge are not going to spot them and point them out to a defendant; you need an experienced DUI attorney to look for the loopholes.

Even if you did drink and drive, an experienced legal counsel may be able to help minimize your legal problems and maximize your opportunities to move ahead. A criminal defense attorney helps to equalize the balance of power between the defendant and the prosecution and works to preserve the constitutional rights that are guaranteed to all defendants in the United States.

The Role of Probation in DUI Sentencing

Sometimes courts want to place a person on probation if they have been convicted of DUI. Probation is a common sentence for people convicted of DUI or DWI, but generally only for second-time offenders. Arizona has some of the longest probation terms for DUI in the United States. For a misdemeanor DUI the court can impose up to 5 years of probation. For a felony DUI the court can impose up to 10 years of probation. If you are facing a DUI charge, an experienced lawyer can assist you with your defense. Contact the law office of Shell & Nermyr for your best chance at beating a DUI. 480-775-4800.

The Statistical Picture

In 1999, the US Department of Justice’s Bureau of Justice Statistics issued a Special Report that provides interesting details about probation in DUI cases.

  • Eighty-nine percent of DUI offenders in the system were on probation, rather than incarcerated.
  • DUI offenders made up almost 14 percent of all people on probation.
  • Two-thirds of those on probation for DUI were first-time DUI offenders.
  • It was much more common for a person to seek alcohol treatment while on probation than while in jail.

Conditions of Probation

Usually, a person who is on probation must report regularly to a probation officer, called an APO (Adult Probation Officer) for monitoring of his or her behavior. As part of a probationary sentence, the judge imposes conditions of probation which usually include:

  • Remain law-abiding;
  • Pay a probation fee;
  • Pay fines;
  • Attend substance abuse counseling
  • Submit to random urinalysis;
  • Do not consume alcohol or take drugs without a valid prescription
  • Serve incarceration time in jail or prison;
  • Community service;
  • Do not drive without a valid drivers license;
  • Mothers Against Drug Drivers (M.A.D.D.) class.

The judge’s discretion about which conditions to impose will depend on the facts of the case and the history of the probationer. Of course, a judge may not abuse his or her discretion and the conditions of probation are limited by other laws and by constitutional protections, such as the prohibition against cruel and unusual punishment. The attorneys at Shell & Nermyr know the law and the constitution and will not let any judge violate our clients’ rights.

If a person who is on probation fails to meet the conditions of his or her probation, the court after a hearing can modify or revoke the probation, require incarceration, impose additional penalties or any combination thereof. Sometimes the period of incarceration imposed after a failed probation can be longer than would have been originally imposed when probation was ordered instead. The criminal defense attorneys at Shell & Nermyr have handled thousands of probation violation hearings. Just because you violated probation does not mean that extra penalties must be imposed. If you are facing a probation violation contact Shell & Nermyr 480-775-4800.

Prosecutors Decide Whether to Pursue DUI Cases in Court

A prosecutor usually becomes involved in a DUI criminal case through a referral from the police, who have investigated, arrested, searched and processed an alleged offender. In making the decision whether to go forward with a case, the prosecutor usually considers three things: whether the case is legally sound, whether it can be proved and the relevant policy considerations. If the prosecutor exercises his or her prosecutorial discretion by deciding not to go forward with a case, it will usually be over. The DUI lawyers at Shell & Nermyr have convinced many prosecutors to not go forward with cases. It is never too early to hire the best criminal defense attorneys.

The prosecutor must be assured that there is enough reliable evidence to prove the DUI charge before he or she will bring the case to trial. For example, if the Breathalyzer® machine malfunctioned or the test results were lost, the prosecutor may decide to dismiss the case because crucial evidence would be missing or substantially weakened.

Policy considerations are always part of the decision to prosecute a particular defendant, because the prosecutor’s job is to serve justice in the public interest, not only to win every possible case. The defendant might have mental or physical problems that make a pretrial diversion program, like alcohol or drug treatment or a suspended prosecution, a better option than conviction. Finally, a prosecutor must consider the limited resources of his or her office when choosing which crimes to pursue.

Prosecutors Represent the Government-the City, County or State-in DUI Cases

The filing of a complaint or other official document by the prosecutor officially starts the DUI court case. The prosecutor appears at the defendant’s initial hearing before a judge to represent the government with regard to pretrial release issues like bail. At trial, the prosecutor is allowed to go first and presents the government’s case against the defendant. The government must prove each element of the DUI charge beyond a reasonable doubt, based on relevant, credible evidence elicited through the testimony of competent witnesses. In DUI cases, the arresting officer is generally one of the key witnesses for the prosecution.

Prosecutors have a lot of power and influence in DUI cases. They take the case from the police and decide whether to pursue it in court; they represent the government in court and pursue a conviction; and they may recommend a particular sentence, if the defendant is found guilty. Prosecuting criminal cases is what these government lawyers do day-in and day-out. Accordingly, if you have been charged with DUI, it is very important that your lawyer is experienced, aggressive and has a reputation of winning trials. Call a knowledgeable DUI and criminal-defense attorney now.

Unreliability of Breath-Test Results in a DUI Case In every state in the US, a driver with a blood-alcohol concentration (BAC) of .08 or higher is presumed to be legally intoxicated for DUI purposes. Each state has also enacted an implied-consent law. Implied-consent laws provide that every licensed driver within the state is considered to have given his or her consent to chemical testing to determine his or her BAC whenever a law enforcement officer has reasonable suspicion of intoxication. In most states, refusal to submit to such a test results in license suspension or revocation.

While a blood test is arguably more reliable, the breath test for BAC is more commonly used in the field because the testing equipment is convenient to transport and because the test is easier to administer, can be used by nonmedical personnel, is less physically intrusive to the person taking the test and produces results faster. However, under certain circumstances, breath tests can be less than reliable as an accurate measure of BAC. It is in the best interest of a DUI defendant to retain a criminal-defense attorney who is thoroughly familiar with possible breath-test weaknesses.

History and Science of the Breath Test

The Breathalyzer® was invented in 1954 to collect evidence of intoxication by measuring BAC through breath analysis. Since that time, several manufacturers have entered into the breath-analyzer market and the science behind the machine has evolved. The word “breathalyzer” is now widely used to refer to these apparatus regardless of manufacturer. Other terms used to refer to these devices include evidential breath tester (EBT), breath analyzer, breath-analysis product, breath-alcohol analyzer and breath-testing device or machine. In addition to Breathalyzer, common brands include Intoxilyzer® and Intoximeter®.

In very basic terms, the breath-test machine is designed to measure the amount of alcohol in a deep-lung breath sample and to use that amount to determine BAC. The four main scientific methods used in the various machines are chemical analysis, infrared spectrophotometry, gas chromatography and fuel-cell detection.

Breath-Test Vulnerabilities

A DUI defendant, usually through an experienced attorney and often with the help of a scientific expert, may be able to challenge the breath-test results in his or her case. Several different factors may call into question the reliability of the results. Depending on the law of the state in which the DUI charges were filed, evidence of a problem with the test result could make the BAC reading inadmissible in court or, if the BAC is still admissible, could cast serious doubt on whether the reading is reliable.

Arguments Shell & Nermyr may make to undermine the breath-test results:

  • The breath tests’ assumption of a 2100-to-1 blood-to-breath ratio may not be scientifically reliable.
  • The test was not administered correctly; for example, the administrator did not warm up the machine to the correct operating temperature or ensure an adequately deep lung sample.
  • The test administrator was not properly trained or qualified.
  • The equipment was not maintained properly, calibrated correctly or cleaned adequately.
  • The result was affected by some characteristic of the driver, such as age; lung function; overall strength and size; a disease or condition such as asthma, diabetes, eardrum rupture, ketosis, emphysema, bronchitis, dental issues, fever or harelip; shock or trauma; certain types of special diets; or hiccoughing, burping, vomiting or hyperventilating. Even severe heartburn could have made the breath results unreliable.
  • The test administrator did not continuously observe the driver for an adequate period before the test to prevent him or her from putting anything into his or her mouth that could affect the result. For example, a product used in the driver’s mouth, such as mouthwash or adhesive, or lip ointment could have affected the test result.
  • Police radio operation generated electromagnetic waves, causing radio frequency interference (RFI) with the testing equipment.
  • The driver was exposed to a gas or vapor before the test that made it unreliable, such as during painting, floor sanding, varnishing or other activity with chemical exposure. Similarly, an outside environmental cause in the surrounding air could have caused a high breath test result.

This long list of potential problems with breath test results is not close to complete. If a person charged with DUI is able to show that something affected the reliability of his or her test results, the state will need to rely more on other types of evidence to prove intoxication. Other types of evidence on which the state may need to rely include witness, officer and driver statements; witness and police observations; or field-sobriety test results.

Other Issues

Other significant issues include:

  • A DUI record can also impact your premiums for or coverage by other types of insurance policies, such as life or medical insurance.
  • After a DUI conviction, you will be considered a high-risk driver. Most states require such drivers to obtain from their insurance companies for filing with the state SR-22 forms, which certify that high-risk drivers are insured.
  • These insurance issues are highly regulated by each state and can vary in how they are handled, so it is important to know the law in your state and what variations to these issues that law may bring.
  • If because of a DUI conviction a person is paying expensive premiums, there may be other ways to lessen the price, such as driving an older car and/or a non-sports car, moving to a safer neighborhood, maintaining a clean driving record, taking a safe-driving class, adding safety equipment to your car, paying all bills on time to boost your credit rating, staying current on your insurance premiums or moving closer to your workplace to shorten the commute.

A DUI conviction can wreak havoc on your automobile insurance coverage. If you are feeling the negative effects of a DUI conviction, an attorney from Shell & Nermyr can help you to sort out the issues and investigate solutions. Contact us at 480-775-4800.


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