The U.S.JusticeDepartmentfiled a civil rights lawsuit againstFerguson,Missouri, on Wednesday to enforce apoliceand courtreformplan after the city said it wanted to amend some aspects of a consent decree it had reached with the federal agency.


TheJusticeDepartmentinitiated a civil rights investigation intoFerguson's policing after an unarmed black teenager was killed by a whitepoliceofficer in 2014. It resulted in a report that was extremely critical ofFerguson'spoliceand court systems.


"The residents ofFergusonhave waited nearly a year for their city to adopt an agreement that would protect their rights and keep them safe," Attorney General Loretta Lynch said at a news conference.


She said the agreement that was decided upon had been painstakingly negotiated andFergusonofficials knew that rejecting it would invite litigation.


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Earlier on Wednesday,Fergusonofficials said they wanted to negotiate further with theJusticeDepartmentoverpolicereforms, after voting on Tuesday to amend the agreement.

Mayor James Knowles told a news conference thatreforms had to be affordable and attainable. "It serves no one's purpose forusto fail," he said.

Ferguson's city council voted on Tuesday to accept thereformagreement, called a consent decree, subject to conditions, including that it not be required to increasepoliceofficers' pay andpolicestaffing levels. It also said it wanted more time to comply with the other terms.

The city became a symbol of problems with policing and race in the United States after 18-year-old Michael Brown was killed byFergusonPoliceOfficer Darren Wilson in August 2014.

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It was one of several killings of black men, mostly by white officers, that started a nationwide debate about theuse of excessive force bypolice, especially against minorities.

Knowles said that only in the last two weeks had the city been able to analyze the costs of implementing the decree.

He and city council members saidFergusonhad already made somereforms, including community policing and a civilian review board to overseepolice.

Civil rights advocates warned that litigation with theJusticeDepartmentcould cost more than implementing the agreement.

"This decision only creates the potential for the type of litigation that creates more financial challenges that will be a burden on poor people," said Rashad Robinson, executive director of Color of Change, a national civil rights organization.