Doctrine of Pith and Substance

The Doctrine of Pith and Substance is a legal principle that is used to determine the true nature or purpose of a law, in order to determine which level of government has the authority to enact it.

This doctrine is often used in situations where a law may relate to more than one area of jurisdiction and it is unclear which level of government has the authority to enact it. For example, if a law is enacted for the purpose of regulating the environment, it might be considered to be within the jurisdiction of the state government, even if it has some incidental effects on federal matters such as interstate commerce or criminal law.

The Doctrine of Pith and Substance is based on the idea that a law should be evaluated based on its substance or purpose, rather than its form or incidental effects. This means that when a court is determining the validity of a law, it will consider the law's true purpose or subject matter, rather than any incidental effects that it may have.

If a law is found to be within the constitutional authority of the enacting government, it will be upheld as valid. If it is found to be outside the constitutional authority of the enacting government, it will be struck down as invalid.