Expert Witnesses in Michigan Domestic Violence Cases

An expert witness may testify in a Michigan domestic violence case, for either side, but only within limits the Michigan Supreme Court set in People v Christel. The expert may explain, in general terms, behavior that is characteristic of people subjected to abuse by a partner. The expert may not say that the complainant was a battered spouse, that the defendant was a batterer or is guilty, or that the complainant was being truthful.^[3]

This page covers the general test for expert testimony, when testimony about intimate partner violence is and is not allowed, the limits on what the expert may say, its use by the defense, and the notice each side gets.

The general test: Rule 702

All expert testimony in Michigan has to pass Michigan Rule of Evidence 702. A witness qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion if the party offering the testimony demonstrates to the court that it is more likely than not that:^[1]

1. the expert's knowledge, whether scientific, technical, or of another kind beyond ordinary experience, will help the trier of fact to understand the evidence or to determine a fact in issue;^[1]
2. the testimony is based on sufficient facts or data;^[1]
3. the testimony is the product of reliable principles and methods;^[1]
4. the expert's opinion reflects a reliable application of the principles and methods to the facts of the case.^[1]

The judge makes that decision, not the jury. If the testimony meets Rule 702, the court must next determine whether its probative value is substantially outweighed by the danger of unfair prejudice. On request, the judge may decide that a limiting instruction is an appropriate alternative to excluding the evidence.^[6]

An expert may base an opinion on facts or data in the case that the expert has been made aware of or personally observed. Those facts or data must be in evidence or, in the court's discretion, be admitted in evidence later.^[7]

A note on terminology

The older cases speak of "battered woman syndrome" or "battered spouse syndrome." In 2024 the Court of Appeals noted that "intimate partner violence" has replaced the prior term.^[5] This page uses the older terms only where a case does.

The Michigan Supreme Court in Christel stated that it did not adopt the battered spouse syndrome as such. What it permits is testimony regarding specific behavior where relevant and helpful to the fact-finder.^[8]

When testimony about intimate partner violence is allowed

Christel, decided in 1995, sets the framework. Expert testimony of this kind is relevant and helpful when needed to explain a complainant's actions, such as:^[2]

• prolonged endurance of physical abuse accompanied by attempts at hiding or minimizing the abuse;^[2]
• delays in reporting the abuse;^[2]
• recanting allegations of abuse.^[2]

The reasoning is that expert testimony is generally needed when a witness's actions or responses are incomprehensible to average people.^[9] A juror may wonder why someone would deny an assault that other witnesses saw, or return to a partner. The expert's role is to tell the jury that such behavior is known to occur, not to tell the jury what happened in this case.

Two threshold requirements apply in every case: the testimony must be relevant, and it must be helpful.^[8] The trial court must also find that the evidence is from a recognized discipline and that the witness is qualified. In Christel the defendant conceded that this kind of evidence is from a recognized discipline.^[9]

When it was allowed: People v Skippergosh

In People v Skippergosh, decided in 2024, the Court of Appeals held that the trial court did not abuse its discretion in admitting expert testimony on intimate partner violence to explain the complainant's behavior after the assaults. The complainant had hidden from police when they arrived to investigate one assault in 2020 and had denied being assaulted in 2021, contrary to the testimony of multiple witnesses.^[10]

When it was not: People v Christel

Christel is also the leading example of the limit. There, because the complainant had not hidden or minimized the abuse, delayed reporting, or recanted, the Supreme Court said "a more direct connection and factual premise is necessary" and deemed the decision to admit the testimony to be error, though a harmless one.^[11]

The lesson is that the testimony has to answer a question the evidence in the case actually raises. If the complaining witness's conduct needs no explanation, there is nothing for the expert to explain.

What the expert may and may not say

Permitted	Not permitted
Explaining the generalities or characteristics of the syndrome, limited to a description of the uniqueness of a specific behavior brought out at trial.[8]	An opinion that the complainant was a battered spouse.[3]
Testifying without being familiar with the facts of the case.[8]	Testimony that the defendant was a batterer or is guilty of the crime.[3]
Describing why a person might hide abuse, delay reporting, or recant.[2]	Any comment on whether the complainant was being truthful.[3]

Skippergosh confirms that the expert need not be familiar with the facts of the case, because the testimony is admissible only to explain generalities.^[8]

Whether an error of that kind affects a conviction depends on the rest of the evidence; in Christel the error was held harmless.^[11]

Expert testimony offered by the defense

The same body of knowledge can support a person who is charged. In People v Wilson, a self-defense case, the Court of Appeals held that expert testimony on battered spouse syndrome may be admitted to support the self-defense claim, but that the expert "is qualified only to render an opinion regarding the 'syndrome' and the symptoms that manifest it, not whether the individual defendant suffers from the syndrome or acted pursuant to it."^[4]

That testimony connects to the legal test for self-defense, which asks whether the defendant honestly and reasonably believed force was needed to protect against the imminent unlawful use of force.^[12] Once there is some evidence of self-defense, the prosecutor must prove beyond a reasonable doubt that the defendant did not act in self-defense.^[13] See Self-defense law in Michigan.

A different kind of defense expert has its own notice rule. A defendant who intends to introduce expert evidence relating to mental illness or intellectual disability bearing on specific intent must notify the prosecutor in writing, on an approved form, and file the notice not less than 30 days before the trial date or at another time the court directs.^[14] In 2026 the Michigan Supreme Court, in People v Madison, overruled its earlier decision that had foreclosed diminished-capacity evidence offered to contest the intent element of a specific-intent crime.^[15] That subject is covered in Defenses to domestic violence charges.

Other experts who appear in these cases

Medical witnesses

Physicians and nurses testify about injuries. In People v Alexander, a child-abuse case, the Court of Appeals said a physician may properly offer an opinion that injuries were inflicted rather than caused by accident or disease, and that where a diagnosis can be drawn from a physical examination, as opposed to a complainant's self-reporting, an expert may testify that a particular injury was not accidentally self-inflicted.^[16] Related issues are covered in Photographs and medical records and Proving or disputing strangulation.

Court-appointed experts

On a party's motion or on its own, the court may order the parties to show cause why expert witnesses should not be appointed, and may appoint an expert the parties agree on or one of its own choosing, if the expert consents. An appointed expert must advise the parties of any findings and may be called and cross-examined by any party.^[17]

Polygraph examiners

A polygraph examiner is not a permitted expert on who is telling the truth. Polygraph results are inadmissible at trial.^[18] See Polygraph tests.

Notice and discovery of experts

On request, a party must provide the names and addresses of the lay and expert witnesses it may call, and expert curricula vitae and reports or summaries.^[19] In a misdemeanor case that subrule applies only if the defendant elects to request discovery under it, and a defendant who does so takes on the same obligation in return.^[20] See Discovery in Michigan domestic violence cases.

When and how a challenge to an expert is heard varies by court.

What people get wrong

"The expert will tell the jury she is a victim." The expert cannot opine that the complainant was a battered spouse or comment on the complainant's truthfulness.^[3]

"The expert examined the people involved." Not necessarily. The expert need not be familiar with the facts of the case.^[8]

"Expert testimony comes in automatically in a domestic violence trial." It has to be relevant and helpful on the facts, and in Christel itself admitting it was error.^[8][11]

"Only prosecutors use this evidence." A defendant claiming self-defense may offer it within the same limits.^[4]

How an earlier statement is weighed against changed testimony, with or without an expert, is covered in Recanting: when the accuser changes the story. People who are witnesses and are unsure what to expect can read What to expect as a witness.