Latin for "for oneself, on one's own behalf." When a litigant proceeds without legal counsel, they are said to be proceeding "pro se." See, e.g. Rivera v. Florida Department of Corrections, 526 U.S. 135 (1999).
The Sixth Amendment guarantees criminal defendants the right to representation by counsel. In 1975, the Supreme Court held that the structure of the Sixth Amendment necessarily implies that a defendant in a state criminal trial has a constitutional right to proceed without counsel when he voluntarily and intelligently elects to do so. See Faretta v. California, 422 U.S. 806 (1975). Thus, an unwilling defendant may not be compelled by the State to accept the assistance of a lawyer. A defendant's right to self-represenatation in federal criminal proceedings is codified in 28 U.S.C. § 1654.
Any waiver of the right to counsel must be knowing, voluntary, and intelligent. The Faretta court stated that "a defendant need not have the skill and experience of a lawyer, but should be made aware of the dangers and disadvantages of self-representation, so that the record will establish that he knows what he is doing and "the choice is made with eyes open." See Faretta. In 2004, the Court acknowledged that it has not prescribed any formula regarding the information a defendant must possess in order to make an intelligent choice. See Iowa v. Tovar, 541 U.S. 77 (2004). According to the Court, determining whether a waiver of counsel is intelligent depends on "a range of case-specific factors, including the defendant's education or sophistication, the complex or easily grasped nature of the charge, and the stage of the proceeding." See Tovar.