Clarkson was best known as the star of Roger Corman's cult film "Barbarian Queen." She was working as a hostess at the House of Blues when she went home with Spector that night.
The coroner's office called it a homicide -- "death by the hand of another" -- but also noted Clarkson had gunshot residue on both of her hands and may have pulled the trigger.
In an e-mail to friends, Spector, 66, termed her death an accidental suicide." He has pleaded not guilty and has been free on 1 million U.S. dollars bail since his arrest. If convicted, he could face life in prison.
Spector, who created the "Wall of Sound," which revolutionized the recording of rock music, was present as members of a prospective jury pool entered the downtown courtroom.
Opening statements are to begin April 30. The judge has ruled the trial can be televised.
Spector produced the Beatles’"Let It Be" album and George Harrison's "Concert for Bangladesh," and has been cited as an influence by Bruce Springsteen and countless other artists.
Spector also wrote such rock classics as "Da Doo Ron Ron," "Be My Baby," "You've Lost that Lovin’Feeling" and "River Deep-Mountain High."
