The guaranty of the right of the accused to the assistance of counsel in making his defence, found in Amendment VI, and in the state constitutions, is intended as an assurance against the recognition in the courts of a practice which at one time prevailed in the criminal courts of England by which a person put on trial for treason or felony was not allowed to be represented by counsel in his behalf. The general rules of procedure in common-law courts allow in civil cases and in prosecutions for lesser crimes that a defendant may have the assistance of counsel if he sees fit, and the exception in prosecutions for treason or felony was unreasonable.

The constitutional right of the accused to be represented by counsel does not necessarily involve the employment of counsel for him at the expense of the state; but it is usually provided by statute that if the accused is unable by reason of poverty to secure the assistance of counsel such assistance shall be furnished at the state's expense.