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Ann Arbor Drunk Driving Law Firm Explains Three Reasons for a Blood Draw During an Arrest

Any Ann Arbor DUI lawyer knows that a person may be required to take a blood test if they are arrested for driving under the influence. In general, there are three instances where a blood test will be completed instead of a breath test:

  1. Search warrant: Blood tests happen when a person who is arrested refuses a chemical test. When arrested for a DUI, the officer will ask if the person will submit to a chemical test to determine if the person consumed alcohol or drugs.  If the person refuses consent to the test, the officer will seek a search warrant for a blood draw. A breath test is voluntarily. A person could be forced to have their blood drawn involuntarily. In reality most people willingly allow their blood drawn once there is a search warrant. As your Ann Arbor DUI lawyer it is recommended that you consent to a blood test if requested. 
  2. Driving Under the Influence of Drugs: A breath test only tests for alcohol. An officer who suspected a driver of being under the influence of drugs must have the person take a blood test.
  3. Michigan State Police is Arresting Officer: Many police agencies and sheriff's departments across the state will have their own breath machine. In a case where a driver is suspected of drinking and consents to a breath test, the driver will be taken back to the police station for the breath test. There are 203 breath test machines across the state. The MSP do not have breath test machines, and will always ask the driver to take a blood test. 

What Types of Drugs Does the Blood Test Look For?

Theoretically, any drug can be found in a person's blood. When a blood test is performed, the MSP laboratory is initially looking for about 50 different drugs. These 50 drugs are the most commonly used substances. Drug examples include marijuana, Xanax, and cocaine. A full list of the substances is below. 

An arresting officer must specifically request the blood be tested for a drug not on the list.

Let's say a person is driving under the influence of psilocybin mushrooms. Ann Arbor DUI defense lawyers do not see a lot of people arrested for driving while on mushrooms. If this person gets arrested for a DUI and the officer has no idea to look for mushrooms in the blood, then the MSP lab will not test for the mushrooms. 

The reasoning behind this is that most people driving under the influence probably took one of these 50 drugs, and any other drugs are used infrequently. It saves money to test this way.

Accuracy in Blood Testing

Blood tests are more accurate than breath tests when it comes to alcohol. A Breathalyzer is like a guess-box. The officers who use them don't even really know how they work. The job of a breath test is to determine blood alcohol content. Yet the breath test machine does not test blood. How does the machine know what the blood alcohol content is? The machine doesn't know - it's making an estimate based on measuring breath. 

A blood test looks at the person's blood alcohol content directly. 

Our Ann Arbor Drunk Driving Defense Lawyer Explains Uncertainty in Blood Testing

Every scientific measurement comes with an amount of uncertainty. A measurement would not be considered scientific without an acknowledgement that the test is not 100% perfect. Let's say a blood test revealed a blood alcohol content of .08. The actual result is not .08. The actual result could be a little bit higher than 0.08 but could also be lower than 0.08. As your Ann Arbor DUI attorney we use this information to challenge the case. 

The MSP Lab Tech

The Michigan State Police is the agency that tests the blood. The person who performs the test is called the lab tech. The lab tech is trained in forensic testing and generally skilled at testifying.

In a DUI trial, the lab tech will testify on several issues. The first issue is whether the blood test was performed correctly. Second is the results of the test. 

The Nurse or Phlebotomist

Along with the lab tech, the person who completed the blood draw will testify in a DUI trial. This witness's job is to testify that the blood draw was completed in the correct manner. A blood draw that is not correctly completed can be used in a DUI trial to create reasonable doubt. 

You Need Ann Arbor DUI Attorney to Challenge Blood Tests

The blood test results can look intimidating to someone facing a DUI charge. They know the tests are more accurate for alcohol than breath tests and believe the case is over. The reality is that the results of any alcohol test doesn't matter. It's important to look at the person as they were driving, walking, and talking during the situation leading to DUI charges. A knowledgeable Ann Arbor DUI attorney will be skilled in the different DUI defenses available for your case. 

What Drugs Will Be Revealed in a Blood Draw?

  • 6-monoacetylmorphine (6-MAM) – (Heroin metabolite)
  • Acetyl fentanyl
  • Acrylfentanyl 
  • Alprazolam
  • Amitriptyline
  • Amphetamine
  • Benzoylecgonine (Cocaine metabolite)
  • Buprenorphine
  • Butalbital.
  • Carfentanil
  • Carisoprodol
  • Chlordiazepoxide
  • Citalopram
  • Clonazepam
  • Cocaine
  • Codeine
  • Cyclobenzaprine
  • Diazepam
  • Etizolam
  • Fentanyl
  • Flubromazepam
  • Flubromazolam
  • Flunitrazepam
  • Furanyl fentanyl
  • Gabapentin
  • Hydrocodone
  • Hydromorphone
  • Ketamine
  • Lamotrigine
  • Lorazepam
  • MDA 
  • MDMA
  • Meprobamate 
  • Methadone
  • Methamphetamine
  • Midazolam
  • Morphine
  • Naloxone
  • Norbuprenorphine
  • Nordiazepam
  • Norfentanyl
  • Oxazepam
  • Oxycodone
  • Oxymorphone
  • Phencyclidine (PCP)
  • Phenobarbital
  • Phentermine
  • Sertraline
  • Sufentanil
  • Temazepam
  • THC-COOH (Marijuana metabolite)
  • Tramadol
  • Trazodone
  • Venlafaxine
  • Zolpidem

If you are charged with a DUI in Michigan, call ArborYpsi Law. We understand the science behind forensic tests. As your Ann Arbor drunk driving defense attorney we will take our knowledge and use it to beat the case.