The Assistance of Counsel Clause of the Sixth Amendment to the United States Constitution provides: "In all criminal prosecutions, the accused shall enjoy the right...to have the Assistance of Counsel for his defence."
The assistance of counsel clause includes five distinct rights: the right to counsel of choice, the right to appointed counsel, the right to conflict-free counsel, the effective assistance of counsel, and the right to represent oneself pro se.
As stated in Brewer v. Williams, 430 U.S. 387 (1977), the right to counsel “[means] at least that a person is entitled to the help of a lawyer at or after the time that judicial proceedings have been initiated against him, whether by formal charge, preliminary hearing, indictment, information, or arraignment.”Brewer goes on to conclude that once adversarial proceedings have begun against a defendant, he has a right to legal representation when the government interrogates him and that when a defendant is arrested, “arraigned on [an arrest] warrant before a judge,” and “committed by the court to confinement,” “[t]here can be no doubt that judicial proceedings ha[ve] been initiated.”
Individuals subject to grand jury proceedings do not have a Sixth Amendment right to counsel because grand juries are not considered by the U.S. Supreme Court to be criminal proceedings which trigger the protections of that constitutional protection.
Subject to considerations such as conflicts of interest, scheduling, counsel's authorization to practice law in the jurisdiction, and counsel's willingness to represent the defendant (whether pro bono or for a fee), criminal defendants have a right to be represented by counsel of their choice. The remedy for erroneous deprivation of first choice counsel is automatic reversal.