Final answer:
The true statement about the Constitutional floor is that states can offer more protection for civil liberties than the U.S. Constitution, but not less. The Fourteenth Amendment ensures that the minimum standard of civil liberties in the U.S. Constitution is applied to the states.
Step-by-step explanation:
Regarding the question of which is true about the Constitutional floor, the correct option is: States may offer more protection for civil liberties than the U.S. Constitution, but not less. The Bill of Rights and subsequent amendments provide a baseline of civil liberties that all states must honor. States can, and sometimes do, extend greater protections through their constitutions and laws.
The Fourteenth Amendment plays a pivotal role by prohibiting states from denying citizens the rights to which they are entitled under the Constitution. This includes the promise of due process and equal protection under the law. Therefore, under this amendment, states are held to at least the minimum standard of rights as outlined in the U.S. Constitution.
Additionally, multiple Supreme Court decisions have applied most of the protections of the Bill of Rights to the states through the process of selective incorporation, which ensures that citizens have consistent civil liberties protections against state actions.