Example: Alabama was the last state to remove its ban on interracial marriage from its statutes in 2000, though this was largely symbolic as interracial marriage was legalized nationwide by the Supreme Court's ruling in Loving v. Virginia in 1967.
There is probably a specific federal law enforcement authority that may or may not be in conflict with the state law. It's unclear if this is a 10th amendment violation for the state or if federal law enforcement is granted this authority