The Trenton (New Jersey) Police Department is tasked with making changes as federal officials say the officers have a pattern of behaviors that violate people's constitutional rights.

It's the result of a year-long investigation by the Department of Justice that looked at things like illegal stops, use of excessive force and arresting people without a legal basis.

The DOJ spent a year conducting what's known as a pattern or practice investigation, which looks into whether the Trenton Police Department has a pattern of conduct that violates federal law. Philip Sellinger, U.S. Attorney for the District of New Jersey, was part of that investigation.

The investigation found Trenton police used unnecessary and excessive force against citizens, 6ABC reports.

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