The U.S. Supreme Court in Indiana v. Edwards (07-208), decided June 19th, 2008:
“Held: The Constitution does not forbid States from insisting upon representation by counsel for those competent enough to stand trial but who suffer from severe mental illness to the point where they are not competent to conduct trial proceedings by themselves. Pp. 4–13.
(a) This Court’s precedents frame the question presented, but they do not answer it. Dusky v. United States, 362 U. S. 402, and Drope v. Missouri, 420 U. S. 162, 171, set forth the Constitution’s “mental competence” standard forbidding the trial of an individual lacking a rational and factual understanding of the proceedings and sufficient ability to consult with his lawyer with a reasonable degree of rational understanding. But those cases did not consider the issue presented here, namely, the relation of that “mental competence” standard to the self-representation right. Similarly the Court’s foundational “self-representation” case, Faretta, supra—which held that the Sixth and Fourteenth Amendments include a “constitutional right to proceed without counsel when” a criminal defendant “voluntarily and intelligently elects to do so,” 422 U. S., at 807—does not answer the question as to the scope of the self-representation right. Finally … 866 N. E. 2d 252, vacated and remanded. BREYER, J., delivered the opinion of the Court, in which ROBERTS, C. J., and STEVENS, KENNEDY, SOUTER, GINSBURG, and ALITO, JJ., joined. SCALIA, J., filed a dissenting opinion, in which THOMAS, J., joined.” (read in full)