The U.S. Department of Justice’s Civil Rights Division and the FBI have launched an investigation into the shooting death of a victim in an alley in the 7000 block of Melrose Avenue in 2008 that involved an off-duty U.S. marshal.

The investigation began after the Los Angeles County District Attorney’s Office concluded that there is insufficient evidence to charge the U.S. marshal, Matthew Itkowitz, with a crime. Itkowitz shot and killed 26-year-old Ryan Gonzalez, who worked at a tattoo parlor on Melrose Avenue, after the victim intervened in an argument between Itkowitz and his wife. After Gonzalez brandished a handgun, Itkowitz allegedly chased him while shooting, and hit him in the back.

Jane Robison, a spokesperson with the Los Angeles County District Attorney’s Office, said investigators had thoroughly reviewed the incident and declined to file a criminal complaint. Itkowitz has claimed self-defense in the shooting, and a surveillance video that captured the incident shows Gonzalez wielding the gun.

“We reviewed it and declined to file because we found that there was insufficient evidence to prove that he [Itkowitz] wasn’t acting in self defense,” Robison said.

The federal authorities launched their investigation to determine whether the shooting was self defense, and if Gonzalez’s civil rights were violated because Itkowitz acted as a law enforcement official. Court records stated that Itkowitz told Gonzalez that he was a U.S. marshal at some point during the fight.

Xochitl Hinojosa, a spokesperson for the U.S. Department of Justice’s Civil Rights Division, said no criminal complaint has been filed, and she declined to comment further because of the ongoing investigation.

The incident occurred on March 5, 2008 after Itkowitz and his wife, Alexandra, had been at an undisclosed restaurant on Melrose Avenue. Itkowitz had been drinking, and admitted to having five shots of tequila, according to investigators. The couple later became involved in a heated argument, and Alexandra Itkowitz left the restaurant and was pursued by her husband. She ran into the alley, where Gonzalez was standing behind the tattoo parlor. Gonzalez allegedly intervened and became involved in a physical altercation with Itkowitz, who was twice knocked to the ground. The surveillance footage also allegedly shows Gonzalez brandishing a gun and threatening Itkowitz, and then walking away. Itkowitz allegedly pulled out his own gun and confronted Gonzalez, who began walking back towards the marshal. Itkowitz then reportedly opened fire and Gonzalez ran. Authorities believe five shots were fired, including one shot that struck Gonzalez in the back and killed him. Itkowitz was questioned by police following the incident but was not arrested. He remains on active duty. Alexandra Itkowitz was not injured in the altercation.

Gonzalez’s family has filed a civil lawsuit against the federal government, alleging that the victim’s rights were violated.