Snyder v. United States was a Supreme Court case that addressed the issue of whether a defendant could be convicted of a crime if the evidence used to convict them was obtained through an illegal search and seizure. The case involved a defendant, Snyder, who was convicted of receiving stolen goods after a search of his home revealed the stolen goods. The search was conducted without a warrant, and Snyder argued that the evidence should not be used against him because it was obtained illegally. The Supreme Court ultimately ruled in favor of Snyder, holding that evidence obtained through an illegal search and seizure could not be used to convict a defendant. The Court reasoned that the Fourth Amendment of the Constitution protects citizens from unreasonable searches and seizures, and that the use of illegally obtained evidence would violate this right. The Court also noted that allowing the use of illegally obtained evidence would encourage law enforcement to disregard the Fourth Amendment and conduct searches without warrants. The ruling in Snyder v. United States established the exclusionary rule, which states that evidence obtained through an illegal search and seizure cannot be used to convict a defendant. This ruling has been used in numerous cases since then to protect citizens from unreasonable searches and seizures.

Justice Field delivered the dissenting opinion in Snyder v. United States, arguing that Congress had exceeded its authority by enacting a law which allowed for the seizure of property without due process of law. He argued that this was an unconstitutional exercise of power as it violated both the Fifth Amendment and Article I, Section 8 Clause 4 of the Constitution. Justice Field further noted that while Congress could pass laws to protect public health or safety, they could not do so at the expense of individual rights such as those guaranteed under due process protections. He concluded his dissent by noting that if this type of legislation were upheld then it would set a dangerous precedent whereby any future acts passed by Congress would be immune from judicial review and thus render all constitutional guarantees meaningless.