The Flint School District is changing its student search policy.
Flint students will still have to walk through metal detectors when school begins next month.
But the American Civil Liberties Union objected to the district's plan to allow students and their backpacks or purses to be searched without cause.
Mark Zimmerman is a professor at the University of Michigan School of Public Health, which houses the Michigan Youth Violence Prevention Center. He says such policies can make students feel like criminals.
"In terms of a developing mind, it breeds distrust. It breeds fear and those things are not healthy," Zimmerman says.
Under the new policy, a student who sets off a metal detector may be searched with a handheld detector and undergo a backpack search.
A 2007 survey found that almost a quarter of Flint's middle school students said they had carried a weapon in the previous month.