Similar fact evidence of other crimes, wrongs, or acts is admissible when relevant to prove a material fact in issue, including, but not limited to, proof of motive, opportunity, intent, preparation, plan, knowledge, identity, or absence of mistake or accident, but it is inadmissible when the evidence is relevant solely to prove bad character or propensity.
Typically, these rules are used by prosecutors to prove a criminal defendant’s motive, opportunity, etc. But, at the federal level, defendants can use “reverse 404(b)” evidence to show, for instance, that someone else had a motive to commit the crime charged. And, as the recent opinion of the District Court of Appeal of Florida, Third District, in Posey v. State, 2021 WL 115437 (Fla.App.3rd 2021), makes clear, Florida similarly allows for “reverse Williams” evidence.
So says Prof. Colin Miller.