Resources and references

On this page, we've tried to collect references and resources bearing on the role of the federal government in using troops to police or control the populace.  We start with relevant provisions of the Constitution itself, as well as other laws and reference materials.  Where we can, we provide PDFs of the materials; our next choice is links you can follow; and, if not available, citations to the materials so you can find them if you are interested.

Article I, Section 8 of the Constitution lays out the powers that Congress has within the federal government.  Here's what it says that directly or by implication governs the use of troops to police or control the populace.

Article I, Section 8

The Congress shall have Power To … provide for the common Defence … of the United States;

…

To declare War, grant Letters of Marque and Reprisal, , and make Rules concerning Captures on Land and Water;

To raise and support Armies, but no Appropriation of Money to that Use shall be for a longer Term than two Years;

To provide and maintain a Navy;

To make Rules for the Government and Regulation of the land and naval Forces;

To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions;

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 United 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;

…

To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof. 

Article II of the Constitution lays out the powers of the President.  Here's what it says that directly or by implication governs the use of troops to police or control the populace:

Article II, Section 1

The executive Power shall be vested in a President of the United States of America. ...

Article II, Section 2

The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States, when called into the actual Service of the United States ... 

Article II, Section 3

[The President] shall take Care that the Laws be faithfully executed, and shall Commission all the Officers of the United States 

Article IV, Section 4 of the Constitution obliges the federal government to provide certain protections to the states:

Article IV, Section 4

The United States shall guarantee to every State in this Union a Republican Form of Government, and shall protect each of them against Invasion; and on Application of the Legislature, or of the Executive (when the Legislature cannot be convened) against domestic Violence. 

A lot of people seem to think that a statute called the "Posse Comitatus Act" bans using federal armed forces for civilian law enforcement, or generally against civilians.  

That's actually not true.  

The Posse Comitatus Act bans using the armed forces for civilian law enforcement except where a law or the Constitution authorizes such activity.  Here, the Insurrection Act itself authorizes the use of the armed forces, so the Posse Comitatus Act simply doesn't apply in cases where the President has invoked his powers under the Insurrection Act.

Here's what it says:

10 U.S.C. section 1385

Whoever, except in cases and under circumstances expressly authorized by the Constitution or Act of Congress,  willfully uses any part of the Army or the Air Force as a posse  comitatus or otherwise to execute the laws shall be fined under this  title or imprisoned not more than two years, or both. 

There's a lot of academic legal writing about the Posse Comitatus Act, but one of the most thorough explanations of how and why it was passed and how it has been applied, along with a lot of information about the origin and use of the Insurrection Act, is contained in a report from the Congressional Research Service.  We've included that below.