Riggs accused of killing rest stop worker near Victor in May 2010

Jeffrey McAdam, 46, of Victor, was shot and killed by Riggs, 33, of Columbus, Neb., as McAdam was working at the rest stop. There is no explanation for the shooting, and none was offered in court Monday.

Riggs pleaded guilty to second-degree murder and admitted to shooting and killing McAdam that day. He declined to speak before he was sentenced to 50 years in prison for second-degree murder.