“There’s a difference between holding people accountable and being cynical,” said Mr. Emanuel, who in his second term as mayor has been battered by criticism over Chicago’s rising violence and mistrusted Police Department. By proceeding with an overhaul of policing, Mr. Emanuel may buy himself some maneuvering room to argue he is bringing the problem under control.



The report described a broad lack of oversight within the department. In some cases, officers reported that they had used force such as punching in order to restrain combative suspects, but video evidence reviewed by investigators frequently showed that officers’ use of force was unnecessary.

“We found that officers engage in tactically unsound and unnecessary foot pursuits, and that these foot pursuits too often end with officers unreasonably shooting someone — including unarmed individuals,” the report said. “We found that officers shoot at vehicles without justification and in contradiction to C.P.D. policy. We found further that officers exhibit poor discipline when discharging their weapons and engage in tactics that endanger themselves and public safety, including failing to await backup when they safely could and should; using unsound tactics in approaching vehicles; and using their own vehicles in a manner that is dangerous.”

Chicago’s police superintendent, Eddie Johnson, said that some findings were “difficult to read” and that he wanted to expand training and mentoring for officers. “While I’m optimistic and hopeful about the direction that we’re heading in,” Mr. Johnson said, “I’m realistic about the fact that there is much, much, much more work that needs to be done.”

Leaders of the union that represents rank-and-file officers questioned the timing of the report and the speed with which the investigation was conducted.