Both Officer Michael Slager and Walter "Lamar" Scott served in the U.S. Coast Guard years before their confrontation on Saturday in North Charleston left Scott dead and led to Slager being charged with murder on Tuesday.
A Coast Guard spokesman confirmed to ABC News that Slager was honorably discharged in 2009 after enlisting in 2003. He was last based at Port Canaveral in Florida.
Scott was enlisted from 1984 to 1986 and was involuntarily separated for a drug-related offense but still received a general discharge under honorable conditions.
Scott's older brother Anthony first revealed his brother's connection to the Coast Guard at a news conference Tuesday night.
"Out of my brothers, he was the most outgoing out of all of us," Anthony Scott said Tuesday night. "He knew everybody. He knew family I didn't know, he had friends I didn't know. He was well known in the community, everywhere."
Scott, 50, was a father of four and a Dallas Cowboy's fan, his brother said. The Scott family's attorney said Tuesday that he had a warrant out for his arrest stemming from outstanding child support payments when he was pulled over by Slager during Saturday's traffic stop, which the attorney said could be a reason why Scott began to run away from the officer.
In the immediate aftermath of Saturday's shooting, Slager's history on the force was reported by ABC affiliate WCIV, which stated he had been a member of the North Charleston Police Department since 2009 and served in the Coast Guard before then. No further information about his service has been made public, and the Coast Guard did not immediately respond to ABC News' calls for comment.
The investigation into the shooting is being handled by the South Carolina Law Enforcement Division, and Slager, 33, was interviewed by their team on Tuesday, just hours before he was charged with Scott's murder, according to North Charleston's mayor and police chief. He appeared at a bond hearing Tuesday night but has not yet entered a plea.
Over the weekend, Slager was represented by attorney David Aylor, who gave a statement to WCIV saying that the incident was "tragic" but that Slager "followed all the proper procedures and policies." That attorney told ABC News on Tuesday he is no longer representing Slager.