Three police agencies in Missouri agreed on Thursday to cut back on the use of tear gas as a means of crowd control, in response to a lawsuit brought by six protesters from the city of Ferguson.

U.S. district judge Carol Jackson dismissed the lawsuit on Thursday at the request of both sides after the settlement was reached. Jackson, however, will supervise for compliance until January 1, 2018.

The restraining order will require police to give "reasonable" warning before deploying the chemical weapon on protesters. The lawsuit was brought against the St. Louis Police, the St. Louis County Police, and the Missouri Highway Patrol by local activists Alexis Templeton, Maureen Costello, Brittany Ferrell, Steve Hoffman, Nile McClain and Kira Hudson.

The lawsuit comes after months of ongoing protests against police brutality and racial profiling, sparked by the police shooting death of unarmed black teenager Michael Brown by a white officer in Ferguson last August.

Three protesters testified at a hearing in December that they were subjected to improper treatment by police, including the use of tear gas.

Thomas Harvey, executive director of Arch City Defenders, which represented the plaintiffs in the lawsuit, said in a statement on Thursday, "This victory rests on the shoulders of the courageous protesters who are tirelessly demonstrating in the streets of Ferguson, and it’s a testament to the powerful movement they have fostered."

Denise Lieberman of the Advancement Project, which also represented the protesters, added, "We had not seen this kind of excessive police force used against protesters since the Civil Rights Movement of the 1960s. The use of tear gas in Ferguson has been a tactic to chill this movement, and today’s consent decree will finally put a stop to those efforts."

Each of the three agencies will also pay the protesters $2,500 in legal costs.