Police officials stress they don't know whether Manson or his followers are connected to the killings, the Los Angeles Times reported. The cases are being reopened, police said, because they occurred near places known as hangouts for Manson and his followers.
Officials said Thursday they hope the tapes, recorded interviews of Tex Watson by his attorney in 1969, can provide some answers.
A federal bankruptcy judge in Texas granted an LAPDs request this spring to review eight cassette tapes containing hours of conversations between Watson and his late attorney. The case stalled after Watson's new attorney appealed.
Los Angeles police then sought a search warrant to get the tapes. U.S. District Richard Schell ruled Oct. 9 the LAPD and Texas authorities could not take the tapes until Watson's appeal was resolved in bankruptcy court.
Manson and his followers were convicted of killing eight people, including actress Sharon Tate, in 1969. Watson was convicted of some of the murders and is serving a life sentence.