What is the legal test used to determine whether a defendant is competent to stand trial?

Appellant now contends the trial court abused its discretion because it applied the wrong legal standard. We disagree. "When a competency hearing has already been held and the defendant has been found to be competent to stand trial, 'a trial court is not required to conduct another competency hearing unless "it 'is presented with a substantial change of circumstances or with new evidence'" that gives rise to a "serious doubt" about the validity of the competency finding. [Citation.]' [Citation.]" (People v. Kaplan

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