The correct answer is: "the Due Process Clause"
The Due Process Clause was introduced in the 14th Amendment to make the Bill or Rights enforceable at the state level and to transform the administration of justice in an institution that protects all US citizens equally. It prohibits state and goverment officials, to deprive any person of its life, liberty or property without obtaining an specific legislative authorization first.
The Supreme Court has subsequently interpreted that this clause provides four types of protections: procedural due process (for civil and criminal cases), substantive due process, against vague laws, and because it constitutes a vehicle for the incorporation of the Bill of Rights.