Void for Overbreadth
If a criminal statute encompasses activity which would be otherwise protected by the U.S. Constitution, a defendant may challenge the provision on grounds that it is overbroad and therefore unconstitutional. The defense is sometimes combined with the doctrine of vagueness but the two doctrines are conceptually distinct.
Overbreadth is most commonly raised when a defendant's activity is protected by another Constitutional right, such as Freedom of Speach. For instance, in Coats v. Cincinnati  the U.S. Supreme Court struck down a criminal statute which made it a crime for three or more persons to assemble on a sidewalk and annoy others. The court determined that the provision was overbroad because it included some activity that would be protected under the First Amendment of the United States Constitution.
- Coats v. Cincinnati, 402 U.S. 611 (1971)