DNA Evidence in Michigan Sex-Crime Cases

DNA enters a Michigan sex-crime case by two statutory routes: evidence collected in a sexual assault evidence kit, and a reference sample that a person arrested for a felony must provide.^[7][1] The law then regulates who may see a profile, how long it is kept, and how it affects the time limit for charges.

This page covers those legal rules. It does not cover the science: testing methods, match statistics and the workings of the national database system are outside the sources this guide relies on. Questions about what a particular laboratory report means belong with a qualified expert.

Where DNA evidence comes from

The evidence kit

A sexual assault evidence kit is a standardized set of equipment and written procedures, approved by the Department of State Police, designed to be administered to an individual principally to gather evidence of sexual conduct.^[8] Under the kit statute, "analyzed" means evaluating items for the presence of a body fluid, cellular material or DNA, followed by testing suitable items at forensic DNA regions for comparison purposes.^[9]

DNA profiles from analyzed kit evidence are uploaded only into the databases at the state and national levels specified by the State Police.^[7] The statutory timetable for collecting and testing kits is in Sexual assault kits: testing deadlines and tracking, and the exam itself in The sexual assault medical forensic exam.

The arrest sample

A person must provide samples for chemical testing for DNA identification profiling if he or she is arrested for committing or attempting to commit a felony, or an offense that would be a felony if committed by an adult.^[1] The statute defines "felony" for this purpose as an offense punishable by imprisonment for more than 1 year or one expressly designated a felony, and "sample" as a portion of a person's blood, saliva or tissue.^[10]

That definition matters for fourth-degree criminal sexual conduct, which the Penal Code labels a misdemeanor but which carries up to 2 years.^[11] The degrees are explained in the overview of the four degrees.

Other routes

Outside those statutes, obtaining a sample from a person who has not been arrested is a search question. A warrant issues on a sworn affidavit when a judge or magistrate is satisfied there is probable cause, and a warrant may be issued to search for and seize evidence of crime or criminal conduct.^[12][13] Consent is an established exception to the warrant requirement, and it must be voluntary.^[14]

What happens to an arrest sample

Event	What the statute says
Arrest for a felony	A sample is collected.[1]
Written notice at collection	The individual must be notified in writing that the sample or profile must be destroyed or expunged if the charge is dismissed, results in acquittal, or is not filed within the limitations period, and that the burden to request destruction is on the arresting agency and the prosecution, not the individual.[3]
No felony charge	The sample must not be forwarded to the State Police; if it is forwarded anyway, the agency must notify the department to destroy it.[2]
Felony charge and district court arraignment	The sample is forwarded to the State Police.[2]
Dismissal, acquittal, or no charge within the limitations period	The State Police laboratory must dispose of the sample or profile when the department receives a written request and a certified copy of a final court order, and must do so not more than 60 days after that notice.[15] That duty does not apply if the department determines the individual has otherwise become obligated to submit a sample, or if evidence relating to another individual would be destroyed.[16]
Conviction	The court must order a $60 assessment.[17]

The baseline rule is permanent retention: except as the section otherwise provides, the State Police must permanently retain the DNA identification profile of an individual arrested for or convicted of a felony.^[15] Any other DNA identification profile obtained by the department must be retained only as long as it is needed for a criminal investigation or criminal prosecution.^[15]

The statute also deals with mistakes. An identification, warrant, arrest or conviction based on a DNA match is not invalidated if it is later determined that a sample was erroneously obtained, a profile was erroneously retained, or disposal did not happen or was delayed, where the error occurred in good faith.^[18]

DNA is treated differently from fingerprints. With an exception the statute makes for charges dismissed before trial, the rule that biometric data and the arrest card are destroyed after a finding of not guilty does not apply to a person who was arraigned for criminal sexual conduct in any degree.^[19]

Who may see a DNA profile

DNA identification profiles received under the state's profiling act may be disclosed only in four ways:^[20]

• To a criminal justice agency for law enforcement identification purposes.^[20]
• In a judicial proceeding as authorized or required by a court.^[20]
• To a defendant in a criminal case if the profile is used in conjunction with a charge against the defendant.^[20]
• For an academic, research, statistical analysis, or protocol developmental purpose, only if personal identifications are removed.^[20]

A sexual assault victim has a separate right to ask the investigating agency about testing in his or her own case: when the kit was submitted, whether a suspect's DNA profile was obtained, whether it was entered into a data bank, and whether there is a match, if the information is available and disclosure would not impede or compromise an ongoing investigation.^[21]

DNA and the time limit for bringing charges

DNA can extend the period in which a case may be charged. For second-, third- and fourth-degree criminal sexual conduct and assault with intent to commit criminal sexual conduct, if evidence of the offense is obtained and contains DNA determined to be from an unidentified individual, an indictment against that individual may be found and filed at any time after the offense is committed.^[4]

Identification restarts a clock. For a second- or third-degree offense committed on or after April 2, 2025, after the individual is identified the indictment may be filed within 15 years after the identification or by the alleged victim's 42nd birthday, whichever is later.^[4][22] For a fourth-degree offense or assault with intent, it is 10 years after the identification or the alleged victim's 21st birthday, whichever is later.^[23] First-degree criminal sexual conduct may be charged at any time with or without DNA.^[24] The full table is in Statute of limitations for sex crimes; older cases are discussed in Delayed reports and old allegations.

How DNA evidence is handled in court

At the preliminary examination

The rules of evidence apply at a preliminary examination, with an exception for certain reports, which are admissible without the author's testimony. Those include a report of the findings of a technician of the State Police forensic science division and a laboratory report.^[25] See The preliminary examination in a CSC case.

At trial

Testimony interpreting a laboratory result is expert testimony. Under Michigan Rule of Evidence 702, a qualified expert may give an opinion if the proponent demonstrates that it is more likely than not that the expert's knowledge will help the trier of fact, the testimony is based on sufficient facts or data, it is the product of reliable principles and methods, and the opinion reflects a reliable application of those principles and methods to the facts of the case.^[6]

Discovery

On request in a felony case the prosecutor must provide any exculpatory information or evidence known to the prosecuting attorney and any police report concerning the case.^[26] A party must also provide, on request, the curriculum vitae of an expert it may call and either the expert's report or a written description of the proposed testimony, the opinion and its underlying basis; and on good cause shown the court may order that a party be given the opportunity to test tangible physical evidence without destruction.^[27] How discovery works in general is covered in the sister guide's page on discovery.

Deadlines are not a suppression rule

A missed kit deadline is not, by itself, a ground to exclude the results. Failure to comply with the kit submission statute is not grounds in any criminal proceeding for challenging the validity of a database match, and an accused or convicted person has no standing to object to non-compliance.^[28][29]

What a DNA result does and does not decide

The legal questions in a criminal sexual conduct case are set by the elements of the offense, and a DNA result bears on some of them and not others. The statutes show this in three ways.

• DNA is not required. The testimony of a victim need not be corroborated.^[5]
• Identity is one issue among several. The model instructions tell jurors the prosecutor must prove beyond a reasonable doubt that the defendant was actually there when the alleged crime was committed.^[30] Where the people involved agree that sexual activity took place and the dispute is about consent, the governing rules are the ones in The consent defense.^[31]
• Evidence about the source of semen has its own rule. The rape-shield statute generally bars evidence of a victim's sexual conduct, but one of its two exceptions is evidence of specific instances of sexual activity showing the source or origin of semen, pregnancy or disease.^[32][33] A defendant who proposes to offer that evidence must file a written motion and offer of proof within 10 days after the arraignment on the information.^[34] See Michigan's rape shield law.

Defenses built on identity are covered in Mistaken identity, alibi and DNA.

DNA testing after a conviction

MCL 770.16 allows a petition for DNA testing after conviction. A defendant convicted of a felony at trial before January 8, 2001 who is serving a prison sentence for that conviction may petition the circuit court to order DNA testing of biological material identified during the investigation, and for a new trial based on the results.^[35] A defendant convicted at trial on or after that date may petition on establishing that DNA testing was done, that the results were inconclusive, and that testing with current DNA technology is likely to result in conclusive results.^[35]

The court must order testing if the defendant presents prima facie proof that the evidence is material to identity and establishes by clear and convincing evidence that a sample is available, that it was not previously tested or will be tested with technology not available at the time of conviction, and that the defendant's identity as the perpetrator was at issue at trial.^[35]

What this page does not cover

The following are outside the sources reviewed, and nothing on this page should be read as stating a rule about them: how laboratories generate and compare profiles; how match statistics are calculated or should be explained to a jury; the operating rules of the national database system; and investigative techniques that rely on genealogy databases. The kit statute refers only to "databases at the state and national levels specified by the department."^[7]