The refrain since 2017 is that you could teach entire classes in a range of areas on “The Law of Donald Trump.” With respect to the Constitution, his administration’s rampant corruption and lawlessness has revived public attention to relatively obscure provisions that the public ignores, does not know about or takes for granted. No one knew what emoluments were before 2017.
The threats to return Sen. Mark Kelly to active Navy duty in order to court-martial him over his video statement (with 5 other Dem Senators) reminding soldiers and officers of their oaths to the Constitution and their duty to ignore unlawful orders introduces two such provisions–Speech or Debate and Incompatibility. On the general illegal-orders issue, see Ret. Gen. Mark Herling explain the different oaths that officers and enlisted swear and the different obligation each bears.
The latter–“no Person holding any Office under the United States, shall be a Member of either House during his Continuance in Office”–should prohibit Kelly from returning Kelly to active duty, as he cannot hold a military (executive) commission and office while serving in Congress.
The former–“for any Speech or Debate in either House, they [Senators and Reps] shall not be questioned in any other Place– might preclude any prosecution of Kelly or the others in the video, as they acted as Senators to inform the public on a matter of government concern (executive oversight). But the Court has held three times the immunity does not protect members’ statements to the public, even when those statements entail legislative or governmental matters and even when the public statements repeat what the member said in the legislature. Josh Chafetz repeats his long-standing call to overrule those cases and extend Speech-or-Debate protection to certain public speech.
And that is before we get to the fact that the First Amendment protects the speech in the video (at least as to non-military crimes). But the leader of the Party of Free Speech is familiar with that.