A federal judge has opted not to impose a finding of prosecutorial misconduct on Justice Department lawyers for their handling of a case against Blackwater security guards involved in a 2007 shooting in Baghdad.

In Federal District Court here last month, Judge Ricardo M. Urbina threw out all charges against the five involved in the shootings, which left 17 Iraqis dead and about 20 wounded.

In that decision, Judge Urbina wrote that in a “reckless violation of the defendants’ constitutional rights,” investigators, prosecutors and government witnesses had inappropriately relied on statements the guards had been compelled to make in debriefings by the State Department shortly after the shootings. The State Department had hired the guards to protect its officials.