In the case of Zerbst, Warden v. Kidwell in 1937, the U.S Supreme Court ruled on a matter concerning habeas corpus and right to counsel. The petitioner, Kidwell was convicted for mail theft without being provided with legal representation during his trial. He later filed a writ of habeas corpus arguing that he had been denied his constitutional right to counsel as per the Sixth Amendment. However, both district court and circuit court dismissed his petition stating that he failed to request an attorney at trial. The Supreme Court reversed these decisions holding that unless defendants competently and intelligently waive their rights, they are entitled to be represented by counsel under federal law regardless if they requested one or not. The ruling emphasized that it is the duty of courts in such circumstances where accused lacks funds or capacity to employ counsel himself/herself; then it becomes mandatory upon them (courts) ensuring presence of competent defense lawyer representing him/her throughout every stage of proceedings from arraignment till final determination.

In the dissenting opinion for Zerbst, Warden, v. Kidwell (1937), Justice Benjamin N. Cardozo disagreed with the majority's view that a defendant in a federal court must be provided counsel if they cannot afford one themselves. He argued that this requirement should only apply when special circumstances exist which could prevent an adequate defense without assistance of counsel. These might include situations where defendants are illiterate or mentally impaired, cases involving complex legal issues beyond common understanding, or instances where there is potential for capital punishment upon conviction. In such scenarios, he agreed that it would be unjust to proceed without ensuring representation for the accused party; however, he did not believe this principle should extend universally to all criminal proceedings regardless of context and complexity.