Which case is cited as the business purpose doctrine: Gregory v. Helvering or Ableman v. Booth?
Gregory v. Helvering Gregory v. Helvering, 293 U.S. 465 (1935), was a landmark decision by the United States Supreme Court concerned with U.S. income tax law. The case is cited as part of the basis for two legal doctrines: the business purpose doctrine and the doctrine of substance over form. The business purpose doctrine is essentially that where a transaction has no substantial business purpose other than the tax avoidance and tax evasion|avoidance or reduction]] of Federal tax, the tax law will not regard the transaction. The doctrine of substance over form is essentially that, for Federal tax purposes, a taxpayer is bound by the economic substance of a transaction where the economic substance varies from its legal form.
Exigent circumstance An exigent circumstance, in the criminal procedure law of the United States, allows law enforcement, under certain circumstances, to enter a structure without a search warrant or, if they have a "knock and announce" warrant, without knocking and waiting for refusal. It must be a situation where people are in imminent danger, evidence faces imminent destruction, or a suspect's imminent escape. Once entry is obtained, the plain view doctrine applies, allowing the seizure of any evidence or contraband discovered in the course of actions consequent upon the exigent circumstances.