In what circumstances will a defendant be found competent to stand trial?

In the absence of an "expert opinion from a qualified and informed mental health expert, stating under oath and with particularity that the defendant is incompetent . . . counsel[, if he doubts defendant's competency,] must make some other substantial showing of incompetence that supplements and supports counsel's own opinion" of incompetency. (People v. Sattiewhite (2014) 59 Cal.4th 446, 465 (Sattiewhite).) Only upon such a showing "does the trial court have a nondiscretionary obligation to suspend proceedings and hold a competency trial. [Citation.] Otherwise, we give great deference to the trial court's decision not to hold a competency trial." (Ibid.)

Notwithstanding counsel's view of the matter, if the court has a doubt about defendant's competency, proceedings are suspended until a determination of competency is made. ( 1368, subds. (b)-(c).) But, whatever the trial court's view on the question of defendant's competence to stand trial may be, once a defendant has shown "substantial evidence of incompetence to stand trial, due process requires that a full competency hearing be held." (People v. Stankewitz (1982) 32 Cal.3d 80, 92 [citing Pate v. Robinson (1966) 383 U.S. 375 [15 L.Ed.2d 815]].) " 'Evidence of incompetence may emanate from several sources, including the defendant's demeanor, irrational behavior, and prior mental evaluations.' " (Sattiewhite, supra, 59 Cal.4th at p. 464.) " 'But to be entitled to "a competency hearing, a defendant must exhibit more than bizarre . . . behavior, strange words, or a preexisting psychiatric condition that has little bearing on the question of whether the defendant can assist his defense counsel." ' " (Id. at pp. 464-465 [citations omitted].)

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