In the case of In re Ruffalo, the U.S. Supreme Court ruled in 1967 that an attorney cannot be disbarred on the basis of a charge not included in original disciplinary proceedings. The court held that due process requires notice and opportunity to defend against specific charges during such proceedings. Ohio lawyer Oreste Ruffalo was initially charged with 14 counts of misconduct by his state's bar association but during hearings, a new charge emerged related to his employment of a non-lawyer who had been contacting accident victims for legal representation - something considered unethical under professional conduct rules. This additional charge became crucial in deciding Ruffalo’s disbarment from practicing law before federal courts, despite it being introduced without prior notice or opportunity for defense preparation. The Supreme Court overturned this decision stating it violated constitutional guarantees as he did not receive fair warning and chance to prepare defense against this particular accusation.

In the dissenting opinion for In re Ruffalo, Justice William O. Douglas argued that attorney Ruffalo was not given fair notice of the charges against him and thus his disbarment violated due process. He contended that one of the charges - hiring a non-lawyer investigator who directly solicited clients - was only added after all evidence had been presented in court, denying Ruffalo an opportunity to defend himself against it. Furthermore, he noted this charge did not clearly violate any specific rule of professional conduct at the time it occurred. Douglas also criticized how Ohio's procedure allowed members of its Board of Commissioners on Grievances and Discipline to act as both investigators and judges in disciplinary cases, which could compromise their impartiality. He believed these issues combined rendered Ruffalo’s trial fundamentally unfair.