Chris Tucker is facing a legal battle with the Internal Revenue Service.According to court documents obtained by ET, the IRS has filed a lawsuit against the actor, alleging that he owes roughly $9.6 million in back taxes, penalties and interest.The lawsuit pertains to finances dating back to 2002 when, according to the docs, Tucker was «one of the biggest stars in Hollywood.»The docs also state that Tucker attempted to pay off his debt three times through monthly installation agreements, but