The Fourteenth Amendment guarantees that no person may be deprived of life, liberty, or property without "due process of the law". By its wording, this guarantee would seem to be simple- in order to take life, liberty or property, the government must go through a legal "process". However, the Supreme Court has expanded on this "procedural" due process guarantee a great deal, by creating the separate notion of "substantive" due process.

The legal process required under the “Procedural” element of due process is fair notice and a hearing by an impartial judge. In order to challenge a government action under this guarantee, an individual must show that they were a) deprived of a liberty or property interest, and b) either no legal process was used, or the process used was unfair or against the public interest.

Substantive due process, unlike procedural, is based on the idea that individuals have certain implied personal rights, and that the government cannot infringe on these rights regardless of the "process" it uses. The primary example of substantive due process rights is the right to privacy. Most people do not realize that the U.S. Constitution does not literally guarantee anyone’s privacy. In fact, the word “privacy” does not actually appear anywhere in the text of the Constitution. It is a judge-made right that is said to be implied by the Constitution’s other guarantees.