(law) the administration of justice according to established rules and principles; based on the principle that a person cannot be deprived of life or liberty or property without appropriate legal procedures and safeguards
Constitution says that nobody can be “deprived of life, liberty, or property without due process of law.”
Madison in 1803, the Supreme Court said that the judicial branch has the power to strike down laws that violate the Constitution, even though another branch of government passed that law.