The right to an independent chemical test in a Michigan OWI case

In Michigan, a driver arrested for OWI who takes the officer's breath, blood or urine test has a legal right to a second test given by a person of his or her own choosing. The law requires police to give "a reasonable opportunity" for that test "within a reasonable time after his or her detention," and the person charged is responsible for getting that sample analyzed.^[1]

This page explains where the right comes from, what police have to say about it, what it does and does not include, and how it connects to the rest of the testing process. For the bigger picture of the post-arrest test, start with the implied consent law guide.

Where the right comes from

The right is in MCL 257.625a(6), the part of the Vehicle Code that governs evidential chemical tests. That is the post-arrest test given at the request of a peace officer who has reasonable grounds to believe the person committed one of the crimes listed in MCL 257.625c(1).^[1] The list covers OWI and the related impaired-driving offenses, including operating while visibly impaired, the under-21 offense, child endangerment, the controlled-substance offense and commercial-vehicle OWI.^[5]

The key sentence reads: "A person who takes a chemical test administered at a peace officer's request as provided in this section must be given a reasonable opportunity to have a person of his or her own choosing administer 1 of the chemical tests described in this subsection within a reasonable time after his or her detention."^[1]

The independent test is different from the roadside preliminary breath test (PBT). The PBT is a screening test at the scene; the evidential test, and the independent test that follows it, belong to the post-arrest stage.^[6][7] See the preliminary breath test guide for the roadside rules.

What the officer must tell you

A person arrested for a 625c(1) crime must be advised of five things.^[8] The first three concern the independent test and the use of results:

1. If the person takes a chemical test of blood, urine or breath given at a peace officer's request, he or she "has the right to demand that a person of his or her own choosing administer 1 of the chemical tests."^[2]
2. The results of the test are admissible in a judicial proceeding and will be considered with other admissible evidence in deciding innocence or guilt.^[2]
3. The person is responsible for obtaining a chemical analysis of a test sample obtained at his or her own request.^[2]
4. If the person refuses the officer's test, a test must not be given without a court order, but the officer may seek one.^[8]
5. Refusing will result in suspension of the license and 6 points on the driving record.^[8]

The statute lists what the advice must cover; it does not prescribe exact wording or a form.^[8]

What the right includes, and what it does not

One test, by someone you choose

The statute speaks of "1 of the chemical tests described in this subsection," meaning a test of blood, breath or urine.^[1][2] The statute does not name who the chosen person must be. For comparison, when blood is drawn at a peace officer's request, only a licensed physician or a qualified person acting under a physician's delegation, in a medical environment, may withdraw it.^[9]

The cost and the analysis are on the person charged

"If the person charged is administered a chemical test by a person of his or her own choosing, the person charged is responsible for obtaining a chemical analysis of the test sample."^[1] The statute does not say that police arrange, pay for or analyze the independent test.^[1]

Not a right to use the State Police laboratory

The Michigan State Police Toxicology Unit tests blood and urine for law enforcement agencies in every county from one location, the Lansing Laboratory.^[10] In People v Green (2015), the Court of Appeals held that a defendant cannot choose a specific MSP forensic scientist to perform the independent test, because "the trial court lacks authority to compel a state agency to perform services it does not offer."^[3] The same case held that the discovery rule, MCR 6.201(A)(6), does not let a court order the MSP to retest its own evidence; it only lets the court give the defendant the opportunity to test tangible physical evidence.^[3][11]

Results of the independent test

Right after the independent-test sentence, MCL 257.625a(6)(d) says: "The test results are admissible and must be considered with other admissible evidence in determining the defendant's innocence or guilt."^[1] The sentence does not say on its face whether it refers to the officer's test, the independent test, or both, and this guide does not interpret it. How any test result is offered at trial is covered in the guide to evidence in OWI cases.

People who refuse the police test

The statute's words give the independent-test opportunity to "a person who takes a chemical test administered at a peace officer's request."^[1] A person who refuses enters a different track. No test may be given without a court order, but the officer may seek one.^[4] The officer sends a written report to the Secretary of State and must give written notice of the right to request a hearing within 14 days of the notice.^[12][13] For a non-commercial driver who does not request a hearing, the suspension is 1 year, or 2 years for a second or subsequent refusal within 7 years.^[14] When blood is drawn under a search warrant, the implied-consent statute does not apply.^[15]

Those rules are explained in the guides on refusing a breath or blood test and search warrants for blood draws.

What if the opportunity is not given?

The independent-test passage in MCL 257.625a(6)(d) states the right but, in the text quoted on this page, does not itself say what a court must do if a driver asked for an independent test and was not given a reasonable opportunity.^[1] This guide has not verified Michigan appellate decisions on that question, so it does not describe a remedy. If the issue arises, it is a question for the judge in the particular case, raised through the motion process described in the guide to motions to suppress.

How the independent test fits with the rest of the evidence

A chemical test result is admissible and is presumed to be the same as the level at the time of driving.^[16] Jurors are told they may infer that, and are also told to consider whether the test was technically accurate, whether the equipment was properly maintained, whether the test was given correctly and whether the person giving it was properly trained.^[17][18] The testing statute also does not limit other admissible evidence about impairment or alcohol content.^[19]

Blood drawn at a hospital for medical treatment after a crash follows its own rule: the analysis is admissible whether or not the person was offered or refused a police test, and the hospital must disclose results to a prosecutor who requests them.^[20]

On a written request filed as the statute describes, the prosecution must furnish the police chemical-test results at least 2 days before trial, and failure to fully comply bars the prosecution from using them.^[21] The discovery and video evidence guide covers the other records that can be requested.

Common misunderstandings

Belief	What the law says
"Police must take me to a lab of my choice and pay for it."	The statute requires a reasonable opportunity; the person charged is responsible for obtaining the analysis.[1]
"I can make the State Police lab retest my blood."	Green held a court cannot compel the MSP lab to retest its own evidence or perform services it does not offer.[3]
"The independent test replaces the police test."	The right applies to a person who takes the police test; it is a second test, not a substitute.[1]
"Refusing the police test still gives me the independent-test right."	The statute ties the right to taking the police test; refusal leads to the court-order and suspension rules.[1][4][14]

Practical points for keeping track

These are record-keeping steps, not legal requirements. Write down, as soon as possible, the time of arrest, the time and type of the police test, whether and when you asked for an independent test, what you were told, and the name of any facility or person who did a second test. Keep receipts and any lab paperwork. The documents to keep after an OWI arrest page lists the paperwork the process itself creates.