Blyew et al. v. United States was a case heard by the United States Supreme Court in 1871. The case involved a dispute between the United States and several individuals who had been convicted of violating the Revenue Act of 1862. The individuals argued that the act was unconstitutional because it imposed a tax on income without apportionment among the states, which was prohibited by the Constitution. The Supreme Court held that the act was constitutional, ruling that the tax was not a direct tax and therefore did not need to be apportioned among the states. The Court reasoned that the tax was an indirect tax, as it was imposed on the privilege of receiving income, rather than on the income itself. The Court also held that the act did not violate the Fifth Amendment, as it did not require individuals to incriminate themselves. The decision in Blyew et al. v. United States established that the federal government could impose taxes on income without apportionment among the states. This decision has been cited in numerous subsequent cases, and has been an important precedent in the development of federal taxation law.

In Blyew et al. v. United States, the Supreme Court was asked to decide whether a criminal conviction could be based on circumstantial evidence alone. The majority of justices held that it could, but Justice Field dissented from this opinion and argued that such convictions should not be allowed unless there is direct proof of guilt beyond a reasonable doubt. He reasoned that allowing convictions based solely on circumstantial evidence would lead to arbitrary results and unjustified punishments for innocent people who may have been wrongly accused or convicted due to insufficient proof of their guilt. Furthermore, he noted that the burden of proving innocence in such cases rests with the defendant rather than with the prosecution which violates basic principles of justice and fairness under law. In conclusion, Justice Field believed strongly in protecting individuals' rights against wrongful conviction by requiring more substantial evidence before convicting someone for a crime they did not commit