Trump does not understand how federal prosecutions work, and by calling for summary execution of the Manhattan terrorist, he has made it harder to put him away.

It is no secret that Donald Trump loathes the orderly application of due process of law, either when it works against him or in favor of people he hates. He has referred to the criminal justice system as a “joke” and a “laughingstock,” and has no qualms about threatening witnesses or firing investigators.

But Trump’s reckless attacks on the law are not just causing chaos in the Russia investigation. They are making it harder to convict people who have clearly committed heinous crimes — including terrorism.

On Tuesday, an ISIS-inspired radical mowed people down in a truck in Lower Manhattan, killing eight people in the worst terrorist attack on New York City since 9/11. The perpetrator, an Uzbek national named Sayfullo Saipov, was captured alive and is clearly dead to rights. He should be easy for U.S. attorneys to convict.

But Trump has needlessly, recklessly inserted himself into the case, and created a nightmare for prosecutors, by calling for Saipov’s execution on Twitter:

 

 

This is horrifically irresponsible. Presidents have to be very careful what they say in public about federal cases, because Department of Justice prosecutors ultimately answer to them.

If a president takes sides too publicly — even in what seems to be a clearly open-and-shut case — defense lawyers can claim the trial is unfair and drag it out, or ask a judge to toss the charges. Charles Manson used this defense to prolong his trial.

Trump’s death penalty tweets follow his comments on Wednesday that he would consider sending Saipov to the Guantanamo Bay detention facility. This makes no sense; it is illegal to send citizens or lawful residents of the U.S. there (or technically anyone, really), and even if he could, there is no point detaining Saipov in a facility where he would not receive a trial and never be sentenced to anything.

It is plainly apparent that Trump does not have any understanding of, or interest in, why criminal defendants have the rights they do. He should have learned this lesson after taking out huge newspaper ads calling for execution of the Central Park Five.

Every time Trump opens his mouth and shares his fantasy view of justice, he makes it that much harder for trained prosecutors to win real justice.