The parents of Michael Brown, the unarmed 18-year-old killed last year by a police officer in Ferguson, Mo., filed a civil lawsuit against the city Thursday.

This lawsuit alleges that the officer’s actions violated Brown’s civil rights, and goes on to state that the city’s broader law enforcement practices “led directly to the unjustified killing.”

Brown was shot and killed last August by Darren Wilson, a Ferguson police officer. This shooting set off frenzied protests in the city, demonstrations that flared up again in November when a grand jury opted not to indict Wilson and again last month when the Justice Department cleared Wilson of any civil rights violations.

The wrongful death lawsuit names the city of Ferguson, former police chief Thomas Jackson and Wilson as the defendants. Lesley McSpadden and Michael Brown Sr., Brown’s parents, are listed in the suit as the plaintiffs.

“The bottom line is simply this….Officer Darren Wilson did not have to use this deadly force on that Saturday afternoon,” Benjamin Crump, an attorney for the family, said while standing with Brown’s parents during a news conference Thursday morning. “We do not believe, based on the forensic evidence and the narrative given, that Michael Brown should have been killed.”

The lawsuit will focus in many ways on Wilson’s testimony before the grand jury and his statements about what took place, Crump said.

The suit also includes the city itself and the former police chief because “they cultivated the mindset” that led to the confrontation and shooting, Anthony Gray, another attorney for the family, said during the news conference.

[Read the 12 key highlights from the Justice Department review of Ferguson’s police force]

The city of Ferguson would not comment on the suit because it involved pending litigation, said Jeff Small, a city spokesman.

Wilson’s attorney is out of the country, his law firm said Thursday, but the firm said its position remains that Wilson’s actions “have been completely reviewed by local, state and federal authorities resulting in the same conclusion.”

Wilson and Jackson are no longer with the Ferguson Police Department. Wilson resigned last year after the grand jury decided not to indict him, while Jackson resigned after the Justice Department released a blistering report that said his police force routinely engaged in racially discriminatory practices.

The civil lawsuit extensively cites the Justice Department report on the police force, saying that it illustrates the “pervasive unconstitutional policing” that led to Brown’s death. After the report was released, the city manager and a key judge also stepped down from their positions. Two police officers and the court clerk also left their jobs after the report showed racially charged e-mails that they had sent and received.

The lawsuit also states that Brown’s hands were “raised in a non-threatening manner” while Wilson was firing at him. The Justice Department review that cleared Wilson of any civil rights violations and corroborated his account ultimately determined that Brown’s hands were likely not raised in surrender when he was shot.

“There is no witness who has stated that Brown had his hands up in surrender whose statement is otherwise consistent with the physical evidence,” the Justice Department concluded.

Brown’s family had said at the time that report was released that they were “saddened” by the decision not to pursue civil rights charges, and attorneys for the family said that they would be filing a civil suit.

Federal law sets a particularly high bar for bringing civil rights charges against police officers, because prosecutors have to prove beyond a reasonable doubt that the officer intended to violate a person’s constitutional rights.

In the new lawsuit, filed in a St. Louis County circuit court, Brown’s family said they are seeking at least $75,000 in compensation for damages in addition to other compensation for punitive damages and legal fees. They are also asking for an order barring Ferguson from using policing techniques “that demeans, disregard, or underserve its African-American population.”

Read more:

The Justice Department’s report on the shooting

Key highlights from the Justice Department’s review of the Ferguson police force

Sari Horwitz and Kimberly Kindy contributed to this report.