Philong Huynh, 41, was convicted in the 2008 sexual assault and murder of 23-year-old Dane Williams.
William's body was found in a San Diego alley near Huynh's home.
Investigators got a break in the case when a Navy Corpsman contacted police claiming Huynh sexually assaulted him.
Huynh was also convicted in that attack.
The Associated Press contributed to this report.