In a statement, Chicago Mayor Rahm Emanuel said expanding the use of body cameras "will help enhance transparency and credibility as well as strengthen the fabric of trust that is vital between police and the community."

The announcement comes during days of protests after the Chicago Police Department released dashcam footage of a city officer fatally shooting 17-year-old Laquan McDonald.

According to WGN, the cameras will reportedly cost $2.2 million. Half will come from the city. The other half comes from a U.S. Justice Department grant. (Video via WGN-TV)

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In May, the DOJ announced it budgeted $20 million for body cameras at police stations nationwide. It was estimated earlier this year that a third of the nation's police departments are using body cameras. (Video via ABC)

While there haven't been many studies on how police body cameras can affect officer safety or the outcome of a court case, the goal is to offer more evidence and another point of view of an incident. Officers are expected to tell those they encounter that they're being recorded.

Chicago officers used body cameras for the first time earlier this year, but authorities say so far the results are promising. (Video via WLS-TV)

This video includes images from Getty Images.