The tape shows politician Pleasant Bridgewater telling Travolta's lawyer that a paramedic who treated the actor's son wants at least $20 million as payment to not release a private document to the media.
Bridgewater and ambulance driver Tarino Lightbourne have pleaded not guilty to extortion charges at the trial that began Sept. 21.
Lightbourne came to Travolta's vacation home on Grand Bahama island when the actor's 16-year-old son Jett suffered a seizure on Jan. 2. He later allegedly threatened to make public a release that Travolta signed to have Jett takendirectly to the airport, even though the youth ultimately died at a local hospital and the document never came into play.
Bahamas police set up hidden cameras at a hotel room to capture Bridgewater's meeting on Jan. 19 with Travolta attorney Michael McDermott.
During the meeting, Bridgewater calls Lightbourne on his cell phone and tells him the lawyer is prepared to offer $250,000. She then tells the attorney that Lightbourne responded by telling her: "My mortgage is more than that."
"It's obvious that you can't handle this deal. I can't do it for $250,000. Just tell me when I can come and get my document from you," Bridgewater quotes Lightbourne as saying.
Prosecutors say the two defendants agreed to accept $10 million in installments over a four-year period before they were arrested.
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