What are the Procedures for Determining Competency to Stand Criminal Trial? It is well established that the criminal trial of an incompetent defendant violates the due process clause of the state and federal Constitutions. (Drope v. Missouri (1975) 420 U.S. 162, 171-172; Timothy J. v. Superior Court (2007) 150 Cal.App.4th 847, 857.) In Dusky v. United States (1960) 362 U.S. 402, the United States Supreme Court set forth the test for determining competence to stand trial as whether the defendant "'has sufficient present ability to consult with his lawyer with a reasonable degree of rational understanding-and whether he has a rational as well as factual understanding of the proceedings against him.'" (Ibid.) Following the constitutional standard, section 1367 provides the following definition of incompetence: "A defendant is mentally incompetent ... if, as a result of mental disorder or developmental disability, the defendant is unable to understand the nature of the criminal proceedings or to assist counsel in the conduct of a defense in a rational manner." ( 1367, subd. (a).) "Due process principles further require trial courts to employ procedures to guard against the trial of an incompetent defendant." (In re R.V. (2015) 61 Cal.4th 181, 188.) If the court determines a trial on competence is necessary, it must suspend the criminal proceedings ( 1368, subd. (c)) and "appoint a psychiatrist or licensed psychologist, and any other expert the court may deem appropriate, to examine the defendant" ( 1369, subd. (a)). Section 1369, which sets forth the procedures for a trial on competence, provides in pertinent part, "If it is suspected the defendant is developmentally disabled, the court shall appoint the director of the regional center for the developmentally disabled ... to examine the defendant." ( 1369, subd. (a), italics added.) During the relevant time period, "developmental disability" was defined as "a disability that originates before an individual attains age 18, continues, or can be expected to continue, indefinitely and constitutes a substantial handicap for the individual," but did not include "handicapping conditions that are solely physical in nature." The term included "mental retardation, cerebral palsy, epilepsy, and autism" and "handicapping conditions found to be closely related to mental retardation or to require treatment similar to that required for mentally retarded individuals ...." (Former 1370.1, subd. (a)(1)(H), as amended by Stats. 1996, ch. 1076, 2.5.)