What did Donald Trump do today?

He floated the idea of suspending a Constitutional right he has no Constitutional right to suspend.

Today, Trump's aide Stephen Miller was asked about reports that Trump will try to suspend the Constitutional right of habeas corpus. He said this:

Well, the Constitution is clear. And that, of course, is the supreme law of the land, that the privilege of the writ of habeas corpus can be suspended in a time of invasion. So [unintelligible] that's an option we're actively looking at. Look, a lot of it depends on whether the courts do the right thing or not. 

Habeas corpus is sometimes described as the right (not the privilege) that makes all other Constitutional rights possible. The "Great Writ" guarantees that anyone taken into custody by the government has the ability to challenge their detention in court—which is to say, to get into court in the first place. Without it, no matter how unjust or illegal that detention is, there is nothing preventing sufficiently determined authorities from effectively "disappearing" anyone into the prison system—or, as Trump has recently tried to do, exiling them to a foreign gulag.

But contrary to Miller's claim, the president does not have the authority to suspend habeas unilaterally. By legislation and case law, that responsibility falls to Congress, and even then only when "in cases of rebellion or invasion the public safety may require it." It has only been suspended four times in all of American history, all of them during occasions of genuine danger during war or imminent threat of rebellion, and even then only in very limited geographical circumstances and for certain kinds of prisoners.

Trump has claimed that the presence of any undocumented immigrants is an "invasion"—although Trump has also been caught giving undocumented immigrants jobs that are the reason for their "invasion" in the first place, so it's hard to say he actually believes that. 

Trump also likes to highlight crimes committed by undocumented immigrants, but as a class they are far more law-abiding than American citizens, and he's never suggested suspending habeas simply because of the presence of dangerous native-born Americans.

 

The writ of habeas corpus has its roots in the Magna Carta, the 1215 legal charter that established in English common law the principle that even kings—a form of hereditary executive leadership the United States does not have—are subject to the law.

Why does this matter?

• Even if the President of the United States was a king—and it doesn't—they still wouldn't be above the law.
  

•  The only reason to tell this obvious a lie about what the Constitution says is if you are planning to violate the Constitution.