What is a Williams Rule motion?

Florida's evidence rule permits evidence of other crimes, wrongs, or acts when relevant to prove a material fact in issue — motive, opportunity, intent, preparation, plan, knowledge, identity, or absence of mistake. It is not admissible solely to prove bad character or propensity.

The practical tension. Prosecutors seek to admit prior conduct by identifying a permissible purpose. The defense argues the stated purpose is a pretext and that the real effect is propensity.

The analysis involves whether the evidence is genuinely relevant to a contested material issue, whether the prior act is sufficiently similar and connected, and whether its probative value is substantially outweighed by unfair prejudice.

Why it matters so much. Williams Rule evidence is frequently the most damaging material in a trial. A jury that hears about similar prior conduct is in a very different position, regardless of the limiting instruction it receives.

These motions are litigated before trial, and the ruling often determines how the case gets tried — or whether it gets tried at all.