United States v. Bond was a United States Supreme Court case that addressed the issue of whether a defendant could be convicted of a crime if the evidence was obtained through an illegal search and seizure. The case involved a defendant, William Bond, who was charged with receiving stolen goods. The evidence against Bond was obtained through a search of his home without a warrant. Bond argued that the evidence should be excluded because it was obtained through an illegal search and seizure. The Supreme Court held that the evidence should not be excluded. The Court reasoned that the exclusionary rule, which prohibits the use of illegally obtained evidence, was not applicable in this case because the search was conducted in good faith and without any knowledge of the illegality of the search. The Court also noted that the exclusionary rule was intended to deter police misconduct, not to punish the defendant. The Court's decision in United States v. Bond established that evidence obtained through an illegal search and seizure can be used in a criminal trial if the search was conducted in good faith and without knowledge of the illegality of the search. This decision has been cited in numerous subsequent cases and has become an important part of Fourth Amendment jurisprudence.

In United States v. Bond, the Supreme Court was tasked with determining whether a defendant could be convicted of an offense under a federal statute that had been repealed before his trial began. The majority opinion held that the repeal did not affect the validity of any indictment or conviction for offenses committed prior to its enactment and thus affirmed the lower court's decision convicting Bond. Justice Field dissented from this ruling, arguing that it violated fundamental principles of justice by punishing someone for conduct which was not criminal at the time it occurred. He argued further that if Congress intended to punish such acts retroactively they should have made their intentions clear in enacting legislation rather than leaving it up to judicial interpretation after-the-fact. In conclusion, he maintained that since no one can anticipate what laws may be enacted in future years, allowing convictions based on statutes passed after an act has already taken place would create uncertainty and injustice in our legal system as well as undermine public confidence in government institutions charged with administering justice fairly and impartially.