Spector, 64, who created rock 'n' roll's "wall of sound" recording technique, is charged with murdering Clarkson at his Alhambra mansion in 2003. He has pleaded not guilty and is free on $1 million bail.
The transcripts, released this week after news organizations including The Associated Press and the Los Angeles Times won a legal battle to unseal them, include testimony from police, Spector's chauffeur and women who said they were threatened by Spector.
Alhambra police Officer Beatrice Rodriguez testified that Spector told officers at his home: "What's wrong with you guys? What are you doing? I didn't mean to shoot her. It was an accident."
"'He changed his story and now he claimed to two separate officers at two different times at Alhambra Police Department that Lana Clarkson had blown her own brains out, that she had committed suicide," Deputy District Attorney Doug Sortino told the grand jury.
In a 2003 interview with Esquire magazine, Spector also suggested that Clarkson, 40, may have shot herself.
Spector's chauffeur, Adriano De Souza, told the grand jury he brought the couple to the producer's mansion and waited outside in the car. At 5 a.m. he heard a sound like a pop, he said, and Spector came outside minutes later holding a gun.
"`I think I killed somebody," he quoted Spector as saying. In the house, De Souza said he saw Clarkson's body.
Three women also told the grand jury that Spector, in separate incidents, had acted recklessly and threatened them with a gun.
The most recent incident came at a 1999 holiday party at a Beverly Hills-area home. Deborah Strand told the grand jury that she saw a man she later learned was Spector flicking ash from his cigar on her boyfriend's dog after it jumped on him.
When she told him, "You can leave," Spector turned around and pointed a gun at her right cheek, she testified.
"He said, 'What are you going to say now?"' she told the grand jury. "He looked at me, and I looked at his bodyguard (who) was standing by the entranceway and I said, 'Get him out of here now.' ... That registered in his head, and he immediately took the gun off of my face, put it away; and in a matter of seconds they left without force. They just walked out, that was it."
Sortino told the grand jurors that the evidence demonstrated that Spector was guilty of implied malice, meaning he acted in such an "inherently dangerous" way that he could be responsible for murder.
A Superior Court judge said in November that Spector's lawyers failed to show how releasing the grand jury transcripts would prevent a fair jury from being chosen for trial. On Wednesday, an appellate court lifted an order staying the release of the documents.