The Due Process Clause of the 14th Amendment has been used to incorporate the Bill of Rights and to make it apply to the states. This has been done on a piecemeal basis, not to the Bill of Rights as a whole.
The Due Process Clause of the 14th Amendment states that no state can
deprive any person of life, liberty, or property, without due process of law…
What the Supreme Court has done is to say that “liberty” includes various rights that are protected by the Bill of Rights. By interpreting the clause in this way, the Supreme Court has required the states to abide by the Bill of Rights.
This has been done in at least two different ways. On the one hand, there is the idea of procedural due process. What this means is that states must act properly before taking away someone’s rights. For example, they must conduct a proper trial or go through the proper legislative process. On the other hand, there is the idea of substantive due process. What this idea essentially says is that states may not take away certain fundamental rights even if they go through proper procedures. For example, in Griswold v. Connecticut, the Supreme Court ruled that the states could not take away the right to use contraceptives regardless of whether they went through the correct procedures for making a law. This view of the Due Process Clause holds that states can never deprive people of fundamental liberties even if they follow due process procedures.