How Long Does a Michigan DUI Investigation Take?
A Michigan DUI investigation usually takes as long as the blood test does. When the evidentiary test is a breath test, the number is known that night. When blood is drawn, the case waits on the Michigan State Police Toxicology Unit, and here in Metro Detroit that is usually about a month, though it can run longer.
As Metro Detroit OWI lawyers for more than 30 years, we hear from people in exactly this spot all the time. Because we handle both DUI defense and license restoration, we can help you use the wait to protect your record and your ability to drive.
Why Does a Blood Test Hold Up a Michigan DUI Case?
Most people picture an “investigation” as detectives out gathering evidence. In a typical DUI case, that is not what is happening. The arrest is over, the police report is written, and the only thing still missing is the lab result.
The reason comes down to how the post-arrest test was done. A breath test at the station produces a reading on the spot. A blood sample has to be sent out for analysis, and the Michigan State Police Toxicology Unit serves the entire state from a single laboratory in Lansing. That one lab handles roughly 16,000 blood alcohol cases a year, so samples from every county end up in the same line.
If the lab is also screening for drugs, which is a separate analysis on top of the alcohol test, those cases can take even longer. We explain how drugged driving cases differ from alcohol OWI cases in a separate article.
Thus, in most of these cases, there is very little actual “investigating” going on. People are simply waiting for the results to come back so the case can be charged.
Will I Be Charged When the Blood Results Come Back?
Here is the simple truth, because false hope does nobody any favors. We almost never see someone’s blood come back clean. In our experience, when the results come back, charges almost always follow.
Before the court can issue a summons or warrant, the prosecutor has to sign a written authorization for it. Michigan law makes a summons, rather than an arrest warrant, the default unless an exception applies, such as the prosecutor asking for a warrant. A summons can simply arrive in the mail at your last known address, with a date to appear in court. If you ignore it and miss your court date, a warrant typically follows.
Sometimes no notice ever arrives, and the first sign of trouble is an outstanding warrant. That is why we notify the court, and sometimes the arresting agency, as soon as we are retained, so you do not miss a summons.
Some people ask whether the prosecutor’s time can just run out. On paper, Michigan allows most charges, including OWI, to be filed within 6 years of the offense. In the real world, these cases get charged when the lab report lands, meaning weeks or, at most, months later, not years later.
What Happens to My Driver’s License While I Wait?
This part surprises a lot of people. When a blood test is pending, the officer takes your plastic license, issues a paper temporary permit, and notifies the Secretary of State that a test result is still pending. That temporary permit does not change your driving status. Whatever driving privileges you had before the arrest stay as they were until the case or the Secretary of State changes them. Michigan law spells out what happens next:
- If the results come back clean, the officer must notify you and mail your license back to the address you gave at the time of arrest.
- If the results show alcohol at or above the legal limit or the presence of drugs, your plastic license is destroyed. Once you are charged, the paper permit stays valid until the charges are dismissed, you are acquitted, or your license is suspended, restricted, or revoked.
- If the case is never prosecuted, the permit is good for up to 90 days.
Keep that paper with you. If your license is returned, it is mailed to the address you gave at the time of arrest, and a summons can be mailed to your last known address. If you move, update your address with the Secretary of State and make sure mail sent to your old address still reaches you.
If you refused the breath test, a separate and strict deadline applies. You have 14 days to request a hearing, or your license will be suspended automatically. We explain how that process works in our article on refusing a breathalyzer or blood test.
The stakes climb if this is not your first offense. A second OWI conviction within 7 years means your license will be revoked, not suspended. A revocation has no end date. You have to wait at least 1 year before you can file for restoration, or 5 years if you had a prior revocation within 7 years, and getting a license back after that takes a formal driver’s license restoration appeal and hearing, not just a fee. Because we handle both sides, we plan the defense with your driving future in mind from day one.
What Should I Do While Waiting for My Blood Test Results?
Don’t wait for the summons to show up. The waiting period is time we can use, and the earlier we get involved, the more options we have. We can take steps to preserve evidence, like body-cam and dash-cam video, that otherwise may be recycled after 30 days. Here is what we tell people in this spot:
- Don’t discuss the case with the police or anyone else, other than your lawyer.
- Write down everything you remember about the stop, the arrest, and the blood draw while it is still fresh.
- Keep your temporary permit with you, and don’t drive on anything else.
Once charges are filed, the prosecution must provide the test results to you or your lawyer on written request. From there, we look closely at everything: how the blood was drawn, who drew it, and how the sample was handled on its way to the lab. Michigan law limits who can draw blood at an officer’s request, and the difference between the roadside test and the post-arrest test matters more than most people realize.
Our first goal is always to get the charge dismissed. If the evidence is strong enough to survive a legal challenge, the focus shifts to working out a favorable plea deal and avoiding as many legal penalties and negative consequences as possible. Avoiding jail is always key, as is working toward a shorter and less burdensome period of probation, rather than something longer and more demanding.
Ultimately, success in a DUI case is best measured by what does not happen to you.
Waiting on Blood Results? Call Now to Discuss Your Situation
If you are waiting to hear whether you will be charged, you don’t have to sit with that uncertainty alone. My team and I have been helping good people out of bad situations in Wayne, Oakland, Macomb, and the surrounding counties for more than 30 years.
Contact our office for a free, confidential phone consultation. A friendly and helpful person will take your call, answer your questions, and explain how things work. We are available Monday through Friday, 8:30 a.m. to 5:00 p.m., and an after-hours answering service takes calls when the office is closed.
You can reach us by calling our office, through our contact form, or use the chat box on our website. To learn more about how we handle these cases, visit our Michigan DUI defense page.