United States v. Morgan was a United States Supreme Court case that dealt with the issue of whether a defendant could be convicted of a crime if the evidence presented at trial was obtained through an illegal search and seizure. The Court held that the evidence was inadmissible and that the defendant could not be convicted. The case arose when the defendant, Morgan, was arrested for possession of a firearm without a license. The arresting officers had conducted a search of Morgan's home without a warrant, which was in violation of the Fourth Amendment. At trial, the prosecution sought to introduce the evidence obtained during the search as evidence of Morgan's guilt. The Supreme Court held that the evidence obtained during the illegal search was inadmissible and that the defendant could not be convicted on the basis of it. The Court reasoned that the exclusionary rule, which prohibits the use of illegally obtained evidence in criminal trials, was necessary to protect the rights of individuals from unreasonable searches and seizures. The Court also noted that the exclusionary rule was necessary to ensure that law enforcement officers did not violate the Fourth Amendment in the future. In conclusion, the Supreme Court held that the evidence obtained during the illegal search of Morgan's home was inadmissible and that the defendant could not be convicted on the basis of it. The Court's decision was based on the need to protect the rights of individuals from unreasonable searches and seizures and to ensure that law enforcement officers did not violate the Fourth Amendment in the future.

In United States v. Morgan, the Supreme Court was tasked with determining whether a tax imposed on distilled spirits by Congress in 1864 was constitutional. The majority opinion held that it was, but Justice Field dissented from this decision. He argued that the power to impose taxes is limited to those enumerated in Article I of the Constitution and does not include an excise tax such as this one. Furthermore, he noted that if Congress had intended for such a broad interpretation of its taxing powers then they would have included language explicitly allowing them to do so when drafting the Constitution or subsequent amendments thereto. Finally, he asserted that even if there were some ambiguity regarding Congressional authority over taxation matters, any doubts should be resolved against granting additional powers since doing otherwise could lead to abuse and tyranny by government officials who may use their newfound authority for personal gain rather than public good.