For starters, the high court will try to clarify when other accusers can testify against a defendant — and when the additional testimony amounts to character assassination.

Lawyers argued that it was "fundamentally unfair" to let prosecutors use Cosby's damaging deposition from a sex accuser’s lawsuit against him at trial.

In Bill Cosby's 2005 1,000-page deposition, he admitted to several affairs and said he used quaaludes to seduce women.