Preemption
A number of states in the United States have "preemption clauses" within state law which block local communities from passing smoke-free ordinances more strict than the state laws on the books. The rationale is to prevent local communities from passing smoke-free ordinances which are viewed as excessive by that state's legislature. Other states have "anti-preemption clauses" that allow local communities to pass smoking ban ordinances that their legislature found unacceptable.
Read more about this topic: Smoking Ban