What is the test for evidence of past criminal conduct in a criminal case?

"As a general rule, evidence the defendant has committed crimes other than those for which he is on trial is inadmissible to prove bad character, predisposition to criminality, or the defendant's conduct on a specific occasion. [Citation.] However, Evidence Code section 1101, subdivision (b), permits evidence of a defendant's past criminal acts when relevant to prove a material fact at issue, such as identity, motive, or knowledge. [Citations.]" (People v. Williams (2009) 170 Cal.App.4th 587, 607.)