Charlie Sheen's lawyer, Yale Galanter, is speaking out on behalf of his superstar client ... claiming that Capri Anderson was never hired for sex, just "entertainment" for the night.

On Good Morning America, Galanter says there "was never a sexual encounter or money exchanged for sexual acts" between his client and Anderson.

Galanter also adds that Capri and her lawyer said they would go on television and "lie about what occurred that night in the Plaza" if Sheen didn't fork over a million dollars.

Gallanter adds that he's "confident" that authorities will determine that the porn star's claims against Sheen are a "complete shakedown."