The U.S. Supreme Court case Maryland v. Soper, Judge in 1925 revolved around the issue of whether a federal judge could be sued by a state for actions taken while performing his official duties. The State of Maryland attempted to prosecute Federal District Judge Morris A. Soper for allegedly allowing an illegal search and seizure during a Prohibition-era raid on the Baltimore Trust Company's building, which was suspected of housing illicit alcohol production operations. Judge Soper had issued warrants authorizing federal agents to conduct searches within the premises based on evidence provided by undercover informants about ongoing violations of prohibition laws inside the building owned by Baltimore Trust Co., leading to several arrests and confiscation of contraband liquor. Maryland argued that these actions violated its sovereignty as well as individuals' Fourth Amendment rights against unreasonable searches and seizures since there were no specific names or locations mentioned in the warrant. However, Justice Oliver Wendell Holmes Jr., writing for a unanimous court, ruled that states cannot sue federal officials acting under color of their office unless it can be shown they acted beyond their authority or in violation of constitutionally protected rights - neither condition being met here according to him. Thus, he upheld judicial immunity from prosecution for acts performed within jurisdictional bounds.

In the dissenting opinion for Maryland v. Soper, Justice McReynolds argued that federal officers should not be immune from state prosecution when they violate state laws. He believed that the majority's decision to grant immunity undermined states' rights and disrupted the balance of power between federal and state governments established by the Constitution. He also expressed concern about potential abuses of power by federal officials who might feel emboldened to disregard local laws knowing they would face no consequences in a state court. Furthermore, he disagreed with the majority's interpretation of certain statutes as granting such broad immunity to federal agents, arguing instead that these provisions were intended only to protect them from liability for acts performed within their official duties and not those which violated criminal law.