The mother of an unarmed black man shot dead by a white police officer has filed a wrongful death lawsuit against the officer and the city. 

Angela Leisure says the death of Timothy Thomas is part of a pattern of civil rights abuses by Cincinnati police, perpetuated by inadequate training and discipline by the city. 

The suit contends that officers "have lied about their actions in fatal shootings to justify a claim of self-defense." 

The suit, filed Wednesday in U.S. District Court, seeks unspecified damages. 

An after-hours message seeking comment from police spokesman Lt. Ray Ruberg was not immediately returned. 

Thomas, 19, was shot to death April 7 as he fled from police trying to arrest him on misdemeanor warrants, mostly for traffic offenses. The shooting sparked three nights of violence in Cincinnati, with dozens of people injured and more than 800 arrested. 

Officer Stephen Roach pleaded innocent to misdemeanor charges Wednesday in connection with the shooting. 

Meanwhile, organizers of a downtown music festival that attracted 40,000 people over two days last year canceled this year's event. Protesters angered by Thomas' shooting had threatened to disrupt the festival, saying it should be canceled out of respect to Thomas. 

"Jammin' on Main" was scheduled to begin Friday in an area near Over-the-Rhine, the neighborhood where Thomas was killed. 

"I don't think Cincinnati is in the mood to be jamming," said the Rev. Damon Lynch III, pastor of New Prospect Baptist Church. "This is the time to be rectifying some of the problems we have as a city." 

Also on Wednesday, black activists told the City Council that they may disrupt a police memorial parade scheduled for May 18. 

"We're concerned, naturally, and we're disturbed that any individuals would disturb our police memorial parade to honor our fallen officers," said Ruberg, the police spokesman. 

Thomas was the 15th black male to die at the hands of Cincinnati police since 1995. The police union president has noted that most of the 15 had threatened officers.