MINNEAPOLIS (AP) - The Minneapolis Police Department is the latest Minnesota law enforcement agency to begin equipping officers with body cameras.

As part of a pilot program being launched Friday, 36 officers will wear the cameras for six to nine months to test their effectiveness. The goal is to issue body cameras department-wide by late 2015.

Mayor Betsy Hodges and Police Chief Janee Harteau say the cameras will enhance transparency and accountability. Hodges says body cameras have been shown to decrease both the use of force and complaints about excessive force.

Harteau calls the cameras "an added tool" for officers.

Officers in Burnsville and Duluth already use the cameras. Both departments say they've worked well.

There are some issues though. Among them, the cameras can be turned off at an officer's discretion. Critics say the cameras should be left on.