Sarmina warned Leck that he could face 25 to 50 years in prison. She noted that Leck rejected a plea deal that came with a 10- to 20-year prison term.
Sentencing is Dec. 2.
Leck, a heavyset man with black mustache and goatee and heavy black stubble, said nothing more than was required.
Behind him was a courtroom packed to standing room with about 100 spectators: Lorenzo's family and friends, officers and members of the Highway Patrol, and police officials including Commissioner Charles H. Ramsey.
Lorenzo's family members declined to comment afterward. They left the Criminal Justice Center escorted by police to a waiting line of patrol cars as a dozen members of the Highway Patrol gunned their motorcycle engines. Lorenzo was a drill-team training instructor with 23 years in law enforcement.
He was married with three children, and had a brother who is a police officer.
Lorenzo had completed his shift and was riding his motorcycle north at 3:15 a.m. July 8, 2012, when he was hit head-on by Leck's car at Cottman Avenue.
Assistant District Attorney Jacqueline Juliano Coelho said that the crash tossed Lorenzo about 21 feet and that the Audi pushed the cycle an additional 130 feet.
"The impact literally ripped him out of his boots," Coelho said. One of Lorenzo's legs was severed, she said, and he had multiple skull fractures and damage to almost every organ.
Coelho said witnesses had to tell Leck to get out of his car, which was on fire. When one witness told him he had killed an officer, Coelho said, Leck replied: "I don't care."
Leck had been drinking for about four hours at a TGI Friday's restaurant in Bensalem, Coelho said. Forty-five minutes after the accident, she said, Leck's blood-alcohol level was 0.218, almost three times the legal threshold for drunken driving.
Lorenzo's family has a suit pending against Leck and the restaurant's parent company, saying the restaurant continued to serve him alcoholic drinks after he was visibly intoxicated.