States may enact their laws so long as they do not violate federal law
Under the Federal Constitution, states reserve their right to enact their own state civil, criminal, and administrative laws, including their own municipal and county laws.
Under our political doctrine of Federalism, there is a legal separation between individual state rights (the right for the state to legislate their own laws) versus federally enacted laws which function to preempt (override) state law should there be a conflict between federal and state law.