In the 1920 Supreme Court case Berger et al. v. United States, the court ruled on a matter of prosecutorial misconduct during a trial for conspiracy to violate espionage laws during World War I. The defendants were convicted in district court but appealed based on alleged prejudicial statements made by the prosecutor and his improper conduct throughout the trial. The Supreme Court agreed with this argument, stating that while prosecutors should be free to prosecute with earnestness and vigor, they must refrain from improper methods calculated to produce wrongful convictions. In its decision, it emphasized that justice is not solely about winning cases but ensuring fairness in proceedings as well - an important precedent for future trials involving prosecutorial misconduct allegations.

In the dissenting opinion for Berger et al. v. United States, Justice Oliver Wendell Holmes Jr., joined by Justice Louis Brandeis, argued that the defendants' convictions should be upheld despite allegations of prosecutorial misconduct. He contended that while the prosecutor's conduct was indeed objectionable and deserving of censure, it did not necessarily warrant a reversal of conviction as long as there was sufficient evidence to support guilt beyond reasonable doubt. The dissenting justices believed that any prejudice caused by the prosecutor's behavior could have been rectified through instructions from the trial judge to disregard such comments or actions during deliberations on verdicts. They also emphasized their belief in judicial restraint and deference to lower courts unless there is clear proof of an abuse of discretion or violation of constitutional rights.