What clause of the Fourteenth Amendment helps apply protections of the Bill of Rights to the states?

The clause of the Fourteenth Amendment that helps extend protections of the Bill of Rights to the states is the Due Process clause. This clause prohibits states from denying any person "life, liberty, or property, without due process of law." Through judicial interpretation, the Due Process clause has been used to incorporate specific rights enumerated in the Bill of Rights, applying them at the state level. This legal doctrine is known as "selective incorporation" and ensures that states uphold the rights guaranteed at the federal level, thus expanding the protection of civil liberties and rights against state infringement.

The Equal Protection clause, while crucial for preventing discrimination and ensuring equality under the law, does not specifically address the application of the Bill of Rights. The Commerce clause relates to economic regulation and trade between states, and the Necessary and Proper clause grants Congress powers to pass laws necessary to execute its functions, but neither of these is concerned with the protection of individual rights as outlined in the Bill of Rights.