In the 1934 case of Mooney v. Holohan, Warden, the U.S. Supreme Court ruled in favor of petitioner Tom Mooney who was convicted for a bombing that resulted in ten deaths during a San Francisco Preparedness Day parade in 1916. The court held that due process is violated when prosecutors knowingly use perjured testimony to obtain convictions or withhold evidence that could prove innocence. This decision came after it was revealed years later that key witnesses had lied and their testimonies were coerced by prosecution officials, leading to an unjust conviction against Mooney and his co-defendant Warren K Billings. Despite this ruling, however, neither man's sentence was immediately overturned; they remained incarcerated until pardoned several years later by California Governor Culbert Olson.

In the dissenting opinion for Mooney v. Holohan, it was argued that while deliberate deception by prosecutors is unacceptable and a violation of due process, not every mistake or error in judgment should be considered as such. The dissent emphasized the importance of distinguishing between intentional misconduct and unintentional errors made during trial proceedings. It also stressed that courts must consider whether any alleged prosecutorial misconduct had a significant impact on the outcome of the trial before deciding to overturn a conviction based on claims of unfairness or injustice. Furthermore, it was suggested that if there were indeed instances where prosecutors knowingly used perjured testimony, these cases should be addressed individually rather than setting an overarching precedent potentially undermining public confidence in law enforcement agencies and judicial systems.