You asked: "What are Trump's legal options with regard to using the military?"
Enabling United States law that provides for the establishment and use of active duty Army, Air Force, and Navy military forces is found in Title 10; that of the National Guard - when operating in state domestic operations under the direction of the state’s governor is found in Title 32. The Posse Comitatus Act of 1878 prohibits members of the U.S. armed forces and civil employees of the U.S. (federal) military from enforcing laws on civilians.
Title 18, specifically additional provisions of the Posse Comitatus Act under USC 1385 and Department of Defense Directive 5525.5 statutorily prohibit the use of Title 10 (active duty) military force in domestic operations, and generally prohibit direct participation in state or federal law enforcement activities. Some of those law enforcement activities would include interdicting vehicles, vessels, and aircraft or conducting surveillance, searches, seizures, and making arrests on behalf of civilian law enforcement authorities. Those limitations do NOT apply to the National Guard or the US Coast Guard; further the governor has the authority place NG soldiers in full-time Title 32 Active Duty status, in a law enforcement capacity, under a chain of command that rests within the state.
The US Congress has enacted some specific exceptions that allow Title 10 Active Duty military to provide information monitoring/collection and use of military equipment and facilities in support civilian law enforcement agencies involved with (1) counter-drug and counter-international organized crime activities, (2) situations or criminal activities involving nuclear and other weapons of mass destruction, that exceed the inherent capability of those law enforcement agencies. Finally (3), as defined by The Insurrection Act, (Title 10, Chapter 13) which allows the President to use Title 10 Active Duty military personnel when requested by a governor or a state legislature to suppress insurrections. It also allows the president to use Title 10 forces to enforce law and maintain order when a rebellion against the federal authority of the U.S. occurs and exceeds the capabilities of federal law enforcement agencies.
Bottomline, unless a riot conditions exceed the capability of a state’s law enforcement agencies AND its respective National Guard forces, AND its governor requests a federal response, you won’t see the president or SECDEF ordering active duty Army involvement.
So, you think he was lying about using the military against civilians? If the Ds dont shut it down, hide and watch. And, he will do it legally.
Some people never learn.
