DALLAS -- A federal judge based in Plano has ruled that the Los Angeles Police Department should be able to obtain decades-old tapes of conversations between a Manson family disciple and his attorney.U.S. District Judge Richard Schell wrote in an order released Sunday that Charles "Tex" Watson waived his right to attorney-client privilege when he allowed his lawyer to sell the eight cassettes to an author nearly 40 years ago for a book about Watson's life.The ruling affirms a bankruptcy judge's decision that Watson, 67, who's serving a life sentence in California for his role in the 1969 murders of actress Sharon Tate and six others, sought to overturn.Watson's attorney, Bill Boyd, died in 2009. The tapes were discovered last year by the trustee handling the Chapter 7 bankruptcy case of the law firm where Boyd was a partner.Los Angeles police Cmdr. Andrew Smith said Tuesday that the department is prepared to send detectives to Texas to pick up the tapes as soon as they are available. However, they will wait until a 30-day window for an appeal passes."We are looking forward to getting these tapes and thoroughly analyzing their contents," Smith said.Smith has said that police believe the tapes could yield clues to unsolved murders.Fort Worth lawyer Kelly Puls, who is representing Watson in the tapes matter, said Tuesday that he will talk to Watson about appealing Schell's ruling."We're going to be looking at all our options," Puls said.Schell said Watson gave up his right to attorney-client privilege when he allowed Boyd to sell a copy of the tapes to chaplain Raymond G. Hoekstra with the International Prison Ministries in 1976.The $49,000 that Boyd received was a partial payment for legal fees. The taped conversations became part of Hoekstra's book Will You Die for Me? The Man Who Killed for Charles Manson Tells His Own Story.Moreover, a previous court filing in which Watson said he's willing to allow police to listen to the tapes "alone constitutes a waiver of attorney-client privilege," Schell wrote.The LAPD sought to use a search warrant to obtain the tapes from the trustee, Linda Payne, in October. But Schell blocked that effort, characterizing it as an attempt to circumvent his order that made the tapes off-limits until he could rule on them.Watson, a native of the small North Texas community of Copeville, was a key figure in the Tate-LaBianca murders, one of the most notorious crimes of the 20th century.