The Michigan State Police says an independent report it commissioned found evidence of racial disparities in traffic stops at about a third of agency posts surveyed.
Researchers with Michigan State University have been working with the state police to identify if race or ethnicity is a factor when officers pull drivers over.
The report suggests the agency's stops conducted during daylight hours were more likely to involve African American and Hispanic drivers in several cities, including Lansing, Grand Rapids, and Flint.
Though the report also says more analysis is needed to confirm these findings.
First Lieutenant Michael Shaw says a separate external review will look at how traffic is monitored to evaluate other potential disparities.
"That's why you kind of bring an independent person in there to take a look at it. So they can kind of determine where we're headed, if we need to change — make some changes to the way that we conduct traffic patrol."
Shaw says future studies will have access to GPS data to enhance analysis of traffic stops.