What the statute requires
Michigan’s no-fault act abolishes most lawsuits against at-fault drivers and keeps three doors open for non-economic damages such as pain, suffering, emotional distress and loss of enjoyment of life. Under MCL 500.3135(1), the injured person must have suffered death, serious impairment of body function, or permanent serious disfigurement.
Since June 11, 2019, MCL 500.3135(5) spells out what “serious impairment of body function” means. The Legislature’s notes say this language codifies the Michigan Supreme Court’s 2010 decision in McCormick v Carrier. The impairment must satisfy all three of these parts:
- Objectively manifested. The impairment is observable or perceivable from actual symptoms or conditions by someone other than you.
- An important body function. The function is of great value, significance or consequence to you. This is personal: the use of your hands matters differently to a mechanic than to a retiree, and the court looks at you.
- Affects your general ability to lead your normal life. The impairment has influenced some of your capacity to live in your normal manner. The court compares your life before and after the crash. It does not have to destroy your ability to live normally, and the statute says there is no temporal requirement for how long an impairment must last.
Impairment is different from injury
This is where most threshold fights happen. Michigan courts repeat that what must be objectively manifested is the impairment, the effect the injury has on how your body works, not the injury or its symptoms. A herniated disc on an MRI is an injury. Lost range of motion, weakness, nerve deficits on testing, and a surgeon’s decision to operate show the impairment.
Pain alone is not enough. McCormick holds that mere subjective complaints of pain and suffering are insufficient, but evidence of a physical basis for the pain can be used to show an objectively manifested impairment. In February 2026 the Court of Appeals, in an unpublished opinion (Jones v Hammons), affirmed dismissal of a case where the plaintiff offered diagnoses, including a radiculopathy finding her own records contradicted, but no evidence that others could observe her limitations. The lesson is practical: the medical records have to describe function, not just diagnoses.
Evidence that tends to prove the threshold
- Imaging (MRI, CT, X-ray) paired with physical examination findings that match it
- Objective testing: EMG and nerve conduction studies, neuropsychological testing, range-of-motion measurements
- Work restrictions, disability slips and activity limits written by treating doctors
- Surgery, injections and other invasive treatment, with the surgeon’s operative findings
- Statements from family, coworkers and friends who saw how your life changed
- Records of what you did before the crash: sports, second jobs, caregiving, hobbies
Gaps in treatment and inconsistent complaints are what insurers look for. Keeping your appointments and telling every provider the same accurate story about your limits does more for this element than anything else you control.
Judge or jury
Under MCL 500.3135(2)(a), whether you have a serious impairment is a question of law for the judge if there is no factual dispute about the nature and extent of your injuries, or if a dispute exists but is not material to the answer. Otherwise it goes to the jury. Defense lawyers often file a motion for summary disposition on the threshold after discovery, so the record has to be built before that point.
The closed-head injury rule
Brain injuries get a specific rule. The statute currently reads: “for a closed-head injury, a question of fact for the jury is created if a licensed allopathic or osteopathic physician who regularly diagnoses or treats closed-head injuries testifies under oath that there may be a serious neurological injury.” The physician must be an MD or DO who regularly diagnoses or treats these injuries. See our brain injury page for how this works in practice.
Pre-existing conditions
A crash that aggravates an old back problem or a degenerative condition can still meet the threshold. The comparison is your life before this crash and after it, so prior records showing you were functioning well are valuable evidence. The defense will argue the impairment came from the earlier condition; your doctors need to address causation directly.
Permanent serious disfigurement
Scarring, amputation and burns can satisfy the threshold on their own as permanent serious disfigurement, without proving a serious impairment of body function. See catastrophic injuries.
What the threshold does not control
The threshold applies to non-economic damages. A claim for excess medical expenses and wage loss above your PIP limits does not require it for Michigan residents. Your own no-fault benefits do not depend on it at all; see PIP medical benefits. And even when the threshold is met, being more than 50% at fault bars non-economic damages.
Three years from the crash. A lawsuit against the at-fault driver must be filed within three years (MCL 600.5805(2)). The evidence that proves the threshold, especially early medical findings, is easiest to gather in the first months.
Sources: MCL 500.3135(1), (2)(a), (5); McCormick v Carrier, 487 Mich 180 (2010); Jones v Hammons (Mich App, Feb. 18, 2026, unpublished); MCL 600.5805(2).
Questions people ask us
What is a serious impairment of body function in Michigan?
MCL 500.3135(5) defines it as an objectively manifested impairment of an important body function that affects your general ability to lead your normal life. All three parts must be shown. The definition was written into the statute in 2019 to match the Michigan Supreme Court’s decision in McCormick v Carrier.
Does my injury have to be permanent to sue for pain and suffering?
No. The statute says there is no temporal requirement for how long an impairment must last. A temporary impairment can qualify if it affected your general ability to lead your normal life while it lasted.
Is a normal MRI the end of my case?
Not necessarily. The question is whether the impairment, meaning the effect on how your body works, is observable or perceivable by someone other than you. Physical exam findings, nerve testing, a surgeon’s observations and medically documented restrictions can all help show it.
Who decides whether I meet the threshold, the judge or the jury?
The judge decides it as a matter of law when there is no factual dispute about the nature and extent of the injuries, or when any dispute is not material. If there is a material factual dispute, it goes to the jury. Closed-head injuries have a special rule that can send the question to the jury on a qualified physician’s testimony.