Here is the money quote:
Clause 16 gives Congress the power "To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the Unit d States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress."(70) Houston's lawyer reasoned that the Congressional power over the national militia is plenary and, therefore, states could not legislate on the subject.
Pennsylvania's lawyers responded that Congressional power over the militia was concurrent with state power, not exclusive. They pointed to the Tenth Amendment, which reserves to states all powers not granted to the federal government.(71) Further, they said, the Pennsylvania statute punishing militia resisters was consistent with the similar federal statute punishing resisters.(72)
The Supreme Court's opinion was delivered by Justice Bushrod Washington, a nephew of George Washington. Justice Washington concluded that, as a general principle, federal legislation regarding the militia was exclusive. Since Congress had enacted a law punishing militia resisters, the states could not enact their own laws about militia resisters.(73)
But, continued Justice Washington, the instant case was different. Here, the question was whether a Pennsylvania court-martial could enforce the federal law. Yes, answered Justice Washington, since the Congressional law creating federal court-martials for militia resisters did not forbid states from enforcing the federal law. And the Pennsylvania statute did not create a new law, but merely enforced the federal one.(74) Thus, the Pennsylvania conviction was upheld.(75)There we have it: The States and their political subdivisions, your local PD and Sherrif's Office, a la Sherrif Joe Arpaio, can arrest all the illegals they can and they have to leave law abiding Americans alone with their guns, including automatic weapons and assault rifles. Take that Obamessiah.