Arizona Criminal Defense Attorney Blog

DUI Blood Test Evidence: How to challenge your DUI blood test results

A good AZ DUI lawyer may be able to challenge blood test results leading to suppression of evidence and a dismissal of your AZ DUI charges.

AZ DUI with Blood Test
If you were arrested for drunk driving in Arizona due to blood test evidence, you should you need to consult an Arizona DUI lawyer who is experienced at challenging blood test result evidence. The best AZ DUI defense lawyers often challenge the prosecutions blood test results taken by the AZ police and processed by their crime lab. In many cases your AZ DUI Attorney will detect flaws, errors, and defense issues regarding the blood test results. The police or personnel conducting the test may have failed to follow prescribed rules of testing, analysis, or preservation, storage, labeling of vials, transport or the processes for which the blood was drawn. Top Arizona DUI attorneys often recognize these violations. When that happens, it can become cause for your defense Attorney to challenge the blood test evidence. In many cases this weakness in the prosecution’s case and leads to suppression of the evidence, and dismissal of your Arizona drunk driving charges. .

Blood Tests for Arizona Drunk Driving
The police officer decides what type of test will be conducted. Options are 1) breathalyzer machine, test 2) blood draw or 3) urine sample.
If the police officer has been properly trained and experienced in proper blood draw procedures involving phlebotomy for criminal investigation such as drunk driving or DUI with drugs, the Arizona courts have upheld the legality and approve the admittance of this evidence. Many police department around the state and sent their officers to classes to become certified.

The police will usually give you a second sample for your defense. If they do not, you should ask them at the time of the blood draw to obtain a sample for you. Then your AZ DUI defense attorney can have the blood retested by an independent lab, while the police send the first sample to the crime lab.

Challenging the Blood Test Results in Arizona

Common reasons to challenge blood tests include but are not limited to the following:
• Flaws with the blood kit used: Sample outside of expiration date; kit was not stored at properly sealed, packed and inspected, stored and maintained at proper temperatures.
• The blood sample vials were improperly labeled, creating questions as to whose blood sample it was drawn from; unauthorized personal labeled the sample.
• Blood sample tainted due to improper or unapproved cleaning agents used by the medical facility or police to prepare your arm for the blood draw.
• Blood draw, analysis, preservation and transport failed to follow required protocol leading to questions as to its accuracy
• Improper preservation of vials or vials used beyond expiration dates. .
• The police sent their sample to the hospital. The busy hospital did not follow police protocol required for prosecution. Hospitals are governed by different entities with different governing rules. They are not required to follow protocol for criminal prosecutions which include rules for chain of custody, proper training and credentials for recognition of tainting due to improper cleaning chemicals, and other rules.
• Police denied your request to take a second sample for your defense attorney. This is a violation of your rights to obtain objective evidence for the sake of accuracy in your defense,
If one or more of these violations or errors exist, your AZ DUI lawyer will recognize it, educate the prosecution and court; present compelling arguments; and file motions in your defense and weaknesses in the State’s case against you. Top AZ DUI lawyers recognize what circumstances present the need to challenge blood results. In many cases this leads to suppression of the evidence on your behalf or a total dismissal of your AZ drunk driving charges.


If you have been arrested for DUI or criminal charges in Maricopa County contact the Law Office of James Novak, for your Free Consultation at (480) 413-1499. Speak directly with experienced Arizona criminal Defense and DUI Defense Attorney and James Novak (Former Prosecutor). Also visit www.arizonacrimialdefenselawyer.com for helpful DUI and criminal defense information.

The Law Office of James Novak is devoted to defending DUI, Drug & criminal charges in Arizona, valley wide within the Greater Phoenix,, Maricopa County cities including Chandler, Tempe , Phoenix, Chandler, Tempe, Gilbert, Mesa, Phoenix Metro, and central Phoenix and Phoenix East Valley Arizona.