Second Amendment
The Second Amendment of the United States Constitution reads: "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
On the one hand, some believe that the Amendment's phrase "the right of the people to keep and bear Arms" creates an individual constitutional right for citizens of the United States. Under this "individual right theory," the United States Constitution restricts legislative bodies from prohibiting firearm possession, or at the very least, the Amendment renders prohibitory and restrictive regulation presumptively unconstitutional. On the other hand, some scholars point to the prefatory language "a well regulated Militia" to argue that the Framers intended only to restrict Congress from legislating away a state's right to self-defense.
Scholars have come to call this theory "the collective rights theory." A collective rights theory of the Second Amendment asserts that citizens do not have an individual right to possess guns and that local, state, and federal legislative bodies therefore possess the authority to regulate firearms without implicating a constitutional right.
https://www.law.cornell.edu/wex/second_amendment
In 1939 the U.S. Supreme Court considered the matter in United States v. Miller. 307 U.S. 174. The Court adopted a collective rights approach in this case, determining that Congress could regulate a sawed-off shotgun that had moved in interstate commerce under the National Firearms Act of 1934 because the evidence did not suggest that the shotgun "has some reasonable relationship to the preservation or efficiency of a well regulated milita . . . ."