Just days after the Academy of Motion Picture Arts and Sciences voted to expel Roman Polanski from its ranks, the director's attorney sent a letter to the organization Tuesday morning, arguing the move was unlawful and threatening to take legal action if Polanski is not granted a hearing. In his letter, a copy of which was obtained by The Times, Polanski's attorney, Harland Braun, said the academy had failed to follow both its own rules and California law in denying the Oscar-winning director a chance to present his own case. "We are not here contesting the merits of the expulsion...