Hassan Elliott was sentenced to 75 years in prison.
RELATED: Remembering Philadelphia Police Sgt. James O'Connor killed in line of duty 1 year ago
He is one of four people charged in connection with the killing.
Elliott entered a guilty plea in federal court back in January. He admitted that he was the one who shot and killed O'Connor.
Sergeant O'Connor was shot while a SWAT team was serving a search warrant on the 1600 block of Bridge Street the city's Frankford section.
He was a 23-year veteran of the force and served on the SWAT unit for 15 years.