In a recent SC Supreme Court case, State v. Perry, the court makes clear what the proper standard is for determining whether prior bad acts fall under the common scheme or plan exception. Click here for a post on 404.
The court first defines “propensity:”
The court then explains why propensity evidence is so powerful and the persuadable effect it can have on a jury:
However, the State may use evidence of prior bad acts (that otherwise would be considered propensity) if it uses it for another reason and not to show that the defendant is acting in conformity with his character.
Because a “prior bad act” can sit in two boxes at once – exception to propensity and propensity – the Court emphasizes that trial courts need to weigh probative vs. prejudicial effect (Rule 403) before allowing in these “prior bad acts.”
To the extent a trial court finds evidence of "other crimes" does serve these dual purposes, the court must determine whether the evidence has sufficient probative force for serving the legitimate purpose that the evidence should be admitted, despite its inherent tendency to serve the improper purpose. This determination is bound up in the trial court's duty to balance—pursuant to Rule 403—the probative value of the evidence for its legitimate purpose against the unfair prejudice that results from its tendency to serve the improper purpose.
Before a trial court lets in the prior bad acts, the court needs to determine that there is a connection to the past act and the current crime charged:
Historically, to justify a finding that evidence of other crimes, wrongs, or acts is offered for a legitimate purpose, and thus should not be excluded pursuant to Rule 404(b), South Carolina courts have required a logical relevancy or connection between the other crime and some disputed fact or element of the crime charged.
History of 404 & State v. Lyle
The Court explains the history in South Carolina of Rule 404(b) and the standard. For almost a century now, Lyle has been the preeminent standard in analyzing whether the prior bad act should be admitted. As the Court points out, the standard that came from this case is an “"acid test" of "logical relevancy" or "logical connection" for admissibility of other crimes”
In 2009, the Court handed down State v. Wallace, which interpreted the 404(b) exceptions as requiring:
"A close degree of similarity establishes the required connection between the two acts and no further 'connection' must be shown for admissibility."
And this is essentially what today’s case is about: the Court overturns the Wallace standard and reinstates the Lyle standard. (The Court also overrules State v. Hallman, 298 S.C. 172, 379 S.E.2d 115 (1989))
To sum up the Court’s ruling: