Jurors deliberated for three days to reach verdicts on 25 counts in connection with the Danziger Bridge shootings case, in which police had allegedly opened fire on a group that was crossing the bridge out of town, then lied about it, saying they had been fired upon and planting a gun on one of the victims.
A 40-year-old man and 17-year-old boy were killed, and four others were wounded.
Seven police officers were charged with civil rights violations, conspiracy charges and weapons charges in the shooting deaths of unarmed civilians after Hurricane Katrina.
The case dragged on after a murder prosecution against the seven officers fell apart as a result of prosecutorial misconduct.
On Friday, the jury convicted four officers of opening fire on unarmed civilians and conspiring with others to cover up their actions. The jury also convicted a fifth officer of overseeing the cover-up, including planting the gun.