Independent DUI Blood Tests Are a Legal Right in Arizona

by Aaron M. Black • September 23, 2020

Blood DrawYou may think that a blood test used in Arizona DUI cases means a slam-dunk conviction, but that is not necessarily the case.

Although blood tests to determine the level of alcohol or drugs in your system are commonly used in Arizona and other states, the accuracy of the test can be suspect. So the best course of action is to have a sample, that is taken at the same time by the same person, for testing at an independent laboratory.

You may not know this but, the U.S. Supreme Court in 2016 ruled that warrantless blood draws are unconstitutional because piercing the skin is far more evasive than a breathalyzer test, which is like “blowing up a party balloon,” wrote Associate Justice Samuel Alito Jr.

He made that remark regarding one of three cases from two states in the high court’s ruling that blood taken without a warrant is unconstitutional, while breath tests are not.

At the traffic stop

You may refuse an officer’s request to submit to a blood test, but if you do your license will be suspended for as long as a year. Or if there is a previous refusal on your record to a blood test within 84 months of the current situation, the suspension time is doubled.

If you refuse the test, the officer will confiscate your license and issue you a temporary permit for 15 days. After 90 days of the suspension, you can apply for a restricted license for driving to work, school and medical appointments.

Refusing to allow a blood draw means the traffic officer must get a judge’s permission to draw blood. This is called a warrant. Securing a warrant does not usually take very long with the technology we have today – maybe 5 minutes.

If you consent to the blood draw your license will be suspended if your blood return with a BAC of .08 or more, or if you have a prohibited dug in your system. However, this suspension will be for 90 days. On day 31 of the suspension you would be able to obtain a restricted license.

You have the right to contest the suspension with the ADOT Executive Hearing Office. But, the only way to escape a suspension in a DUI case is to with the hearing with ADOT and win the DUI.

The blood draw

Other than a medical technician drawing your blood, Phoenix and its neighboring cities have several police officers who are trained in the proper procedures for blood draws and a few of these are even certified phlebotomists.

Some communities have especially equipped vans that can be summoned to the traffic stop or the DUI suspect can be taken to a hospital or a police station to have blood drawn.

Blood draw must be taken within two hours, under Arizona law, to obtain an accurate level of how much alcohol or drugs are in the blood sample.

If the blood draw happened after two hours, chemists and toxicologists can employ “retrograde extrapolation.” That is a process using mathematics and science to determine what the blood alcohol level had been at two hours even though more time had passed. The result of this measurement will be used as evidence by the prosecution.

Independent blood test

Blood is drawn from the suspect and stored in a vacuum sealed container called a vacutainer. These vials contain additives selected for the various types of analysis, such as alcohol or drugs, and have chemicals that prevent bacterial contamination during storage.

The defense has the right to have an independent laboratory test a second vial of blood drawn by the police. The technician drawing blood fills two vials, one for the prosecution and the second for the defense. In cases where a second vial is not used, the state must share its sample with the defense. It does not take much blood to conduct the analysis, so a single vial holds enough to conduct more than one test.

However, the defense in choosing to retest the blood runs the risk of having the second test confirm the result of the first and that would bolster the state’s case.

Common issues with DUI blood tests

Storage: The vacutainers have seals that have expiration dates to prevent fermentation during storage while cases move through the legal system. If a vial’s seal has expired, the fermentation produces alcohol which will raise the blood-alcohol level of the test.

Drawing blood: Technicians drawing blood can make mistakes that eschew the results. If the technician uses alcohol to clean the injection site, that can impact the test. A blood sample taken in a hospital setting is a medical procedure, but additional steps used by a forensic lab are necessary to reach an accurate result.

Problems with procedure: The state needs to establish a “chain of custody.” The chain tells a history of the blood sample’s storage including who specifically was in charge of the sample. Data omissions and errors can eliminate the blood test from the state’s evidence.

Laboratory mistakes: Law enforcement is a primary customer of forensic labs and these people get to know one another and develop a sort of partnership. The technicians might sway the result and blood samples have been intermingled or switched intentionally or accidentally.

Testing equipment errors: Sophisticated testing devices that are not properly calibrated or maintained can render inaccurate results. Forensic labs may not always have sufficient oversight to avoid mistakes. Much time can pass between the blood draw and entering the testing results into evidence taking as long of two months and sometimes longer in difficult DUI and drug cases.

Defending your case

The technical aspects of blood draw evidence necessities an experienced criminal defense attorney to ensure you can have a second blood test by arranging for the blood split and to ensure your Constitutional rights are protected. My goal is always a dismissal.

If you are facing a felony, a conviction will harm or ruin your way of life. So, get legal representation promptly.

Confidential case evaluation

If you had blood taken by authorities, it is in your best interest to arrange for a confidential case assessment without any obligation to use me for your defense. To arrange for your consultation, call 480-729-1683 anytime day or night, weekends or holidays. We can meet by phone, text, and online at FaceTime in the pandemic.

I have a history of aggressively challenging the state’s case while providing personalized service. You will always be talking to me not an assistant. I defend DUI cases in Maricopa and its surrounding counties in justice, municipal, state, and federal courts.


About the Author

Aaron Black Phoenix DUI LawyerAaron Black is the founder and sole attorney of the Law Office of Aaron Black. Located in Phoenix, Arizona, his DUI and criminal defense law firm provides legal services to people who have received felony or misdemeanor charges from the state.

Aaron has developed a strong interest in defending people who have been arrested and received criminal charges for driving under the influence. With his professionalism and knowledge of Arizona DUI and criminal law, he has acted as a check and balance on the police, prosecution and courts and has protected a great number of his clients from excessive and unfair sentencing.

Along with DUI defense, Aaron handles a range of other criminal defense matters, including aggravated assault, burglary, domestic violence, drug possession, drug trafficking, fraud defense, insurance fraud, sex crimes, and white-collar crime cases.

After graduating college in 2003 from the University of Arizona, Aaron decided to pursue a law degree. He followed a family long tradition and went to the University of South Dakota School of Law where he pursued his goal of becoming a criminal defense lawyer.

After passing the Arizona and South Dakota bar exams, Aaron joined the Maricopa County Office of the Public Defender where he defended hundreds of people charged with serious criminal offenses. His work as a public defender helped him sharpen his litigation skills and gave him a unique insight into the Arizona criminal justice system.

Over the course of his 15-year legal career, Aaron has spent a considerable amount of time in both Arizona justice, municipal, state and federal courts. He has argued over 50 jury trials, tried over 100 bench trials and has become one of the highest-rated criminal and DUI defense attorneys in Phoenix and the surrounding areas. He has received a 10/10 rating from the legal directory Avvo because of his legal background and successful case record. Since 2014, he has received the Super Lawyer rating for his work as a Phoenix DUI Attorney and criminal defense attorney.

You can review Aaron’s Attorney Bio page for more information about his background, education and experience as a Phoenix DUI and criminal defense attorney.
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