4US Federal Rules of Evidence 611(a) - (2) ;California Evidence Code §765(a).
5US Federal Rules of Evidence 403.
6US Federal Rules of Evidence 401, "Relevant evidence" means evidence having any tendency to make the existence of any fact that is of consequence to determination of the action more probable or less probable than it would be without the evidence.
7California Evidence Code 210, "Relevant evidence" means evidence, including evidence relevant to credibility of a witness or hearsay declarative, having any tendency in reason to prove or disprove any disputed fact that is of consequence to the determination of action.