So far, common law has not been exercised fully because of the ignorance of the people about it, and because the government people like their assumed power and try to hide the common law of the people.
That, however, is the best part: if PotUS asserted his pre-U.S. Constitution rights (while retaining his command of the post-U.S. Constitution U.S. armed forces) as a man (that "just so happens" to "have the run" of a massive nuclear, chemical, and biological arsenal), then the U.S. would become a military dictatorship - full stop.
I didn't realize that this was going to be so difficult for people to understand.
If a man inside government (a government agent, a military man, a governmental official), or if a man outside of government, harms another man or his property, it is man harming man. If the perpetrator is inside government, since government can't do anything except that it is activated by a man, it is the man that does it.
The injured man or his relatives can sue the perpetrator one of two ways. They can sue him via an administrative hearing. They can sue him via common law because it was a man that did it.
If the injured man or his relatives sue the perpetrator under administrative law, the whole case will be decided entirely by the government. The government can decide any way it wants, guilty or not guilty, or partially guilty. All the injured man or his relatives do is make noise in an administrative hearing.
In a common law hearing, there are three things that might happen:
1. The evidence and the witnesses might be overwhelming and the judge would be required to declare guilt (or innocence if there was no strength in whatever was brought against the perpetrator);
2. The judge might be given the authority by the people bringing the suit against the perpetrator, to judge according to the way the judge interprets the evidence and what the witnesses say;
3. There might be a jury trial where the perpetrator is judged entirely by the jury.
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Obviously, if the man doing that harm is personally strong enough, he might be able to thwart all governments and all people. We are talking sci-fi here, like Iron Man.
There are some people in, say, the military, that might be influential enough in military circles, that they can do harm and damage to the world without true governmental authority. Obviously, if such a man pulls some switches, and launches some nukes, the damage will have been done no matter how many times he is prosecuted, found guilty, and executed later.
EDIT: In a common law of the people hearing, the people bringing the suit create the rules of court. Throw the government's Rules Book out the window.