Officer Dominic Luca makes a joke saying he's from the SLA (Symbionese Liberation Army.) The Symbionese Liberation Army was an American left-wing militant organization active between 1973 and 1975 in the United States.
The part about a cop killer dancing a jig over the dead body was based on a real incident on January 27, 1971 when the Black Liberation Army assassinated police officers Gregory Foster and Rocco Laurie in New York City.