General Flynn is on the outside looking in.
There's no mechanism for declaring martial law given the circumstances in the tweet he re-tweeted.
"....Martial law can be imposed when civil rule fails, temporarily being replaced with military authority in a time of crisis. Though rare, there have been a number of notable U.S. cases where martial law came into play, including in times of war, natural disaster and civic dispute...."
"....While no precise definition of martial law exists, a precedent for it exists wherein, “certain civil liberties may be suspended, such as the right to be free from unreasonable searches and seizures, freedom of association, and freedom of movement. And the writ of habeas corpus [the right to a trial before imprisonment] may be suspended..."
"....Martial law may be declared by both the president and by Congress. State officials may also declare martial law, according to the Brennan Center for Justice, however, 'their actions under the declaration must abide by the U.S. Constitution and are subject to review in federal court'...."
"....Throughout the course of U.S. history, federal and state officials have declared martial law at least 68 times...."
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