Stephon Clark was shot eight times by officers on March 18, and at least six of the bullets entered his back, an expert who conducted a second, independent autopsy said at a press conference Friday.
Clark was unarmed when two officers killed him.
Hundreds attended the 22-year-old's funeral Thursday and protesters again took to the streets. Meanwhile, community leaders continue to call for peace and reconciliation following Thursday's services, when Clark was laid to rest.
Stephon Clark
Lawyers for the family of Stephon Clark told CBS News they plan to file a federal lawsuit as soon as Friday over his death in a police shooting.
The family's attorney, Ben Crump, on Friday released results of the independent autopsy.
The autopsy was conducted this week by former San Joaquin County forensic pathologist Dr. Bennet Omalu.
The Sacramento County coroner has not released details of its autopsy.
Omalu said he found a total of eight gunshot wounds on Clark's body. Six of the bullets entered in his back, Omalu said.
The seventh gunshot wound was slightly to the side of his body but towards the back, according to Omalu.
"You can reasonably conclude he received seven gunshot wounds from his back," Omalu said.
He was also shot in the neck and thigh, Omalu said.
Each one of the bullets could have been fatal, Omalu said.
Clark received injuries to his aorta and suffered "massive bleeding," Omalu said. The bullets struck his lungs and vertebrae, Omalu said.
He said his findings indicate Clark was not facing the officers when he was shot.
"During the entire interaction, he had his back to the officers, not his front," Omalu said.
© 2018 CBS Interactive Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.