Report: Mel Gibson's Ex-Girlfriend Demanded $10M

They're in a bitter child custody battle, which moved inside a Los Angeles courtroom Thursday, though neither of them attended the session.

Their eight-month-old daughter, Lucia, is the subject of the dispute, but tapes apparently recorded by Grigorieva, 40, have been in the media spotlight.

The fifth such tape, another expletive-filled rant by the man alleged to be Gibson, has him claiming he's spent $5 million on Grigorieva and calling her a gold-digger.

But, as CBS News Correspondent Ben Tracy reports, the Oscar-winner's lawyers assert the tapes have been edited, and at least one forensics expert agrees.

During the closed court session, Tracy says, attorneys for Grigorieva contended phone calls like the ones in the recordings are the reason Gibson can't be trusted.

In the latest, the man is heard saying, "I like to show you what mean really is, b**ch, c**t, whore, gold-digger. All true. You f***ing proved it to me."

The L.A. Sheriff's Department is investigating Gibson for domestic violence. Grigorieva has accused him of hitting her and waving a gun in her face.

Authorities received tapes from the court Thursday, though no one was saying whether the tapes they got included the ones RadarOnline posted.

"We will secure them, book them in to evidence," Steve Whitmore, of the Los Angeles County Sheriff's Department, told CBS News. "We will then begin the process of reviewing them, analyzing them."

But Gibson's lawyers allege that the phone calls have been edited, and forensic expert Frank Piazza says they have a point.

One he pointed to "definitely has edits, deliberate edits," Piazza told CBS News.

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