President Trump, rarely at a loss for words, chose silence during his deposition today at the Manhattan offices of New York’s state attorney general. Mr. Trump was subpoenaed as part of a civil suit snooping around as to whether the company that bears his name inflated assets in pursuit of tax benefits and favorable loans. In asserting his Fifth Amendment right, Mr. Trump condemned the campaign against him — and eloquently, too.

This approach is a volte–face for Mr. Trump, who in 2016 asked “If you’re innocent, why are you taking the Fifth Amendment?” Today, he conceded, “Now I know the answer to that question  — when your family, your company, and all the people in your orbit have become the targets of an unfounded, politically motivated Witch Hunt supported by lawyers, prosecutors, and the Fake News Media, you have no choice.” 

Good for Mr. Trump, we say. The attorney general, Letitia James, has made pursuit of Mr. Trump her equivalent of the white whale that obsessed Captain Ahab in “Moby Dick.” Even before taking office, she campaigned on promises to bring Mr. Trump to justice, vowing — before a nanosecond of an investigation — “I will be shining a bright light into every dark corner of his real estate dealings, and every dealing, demanding truthfulness at every turn.”

During her campaign, General James announced that she would “never be afraid to challenge this illegitimate President” and vowed to “see what we can do legally” given that he “engages in business in New York.” Even as a parallel criminal case pursued by District Attorney Alvin Bragg was faltering, General James carried on a political campaign. Mr. Trump is no fool in saying that he would “never be treated fairly by these people.”

It’s not just General James’s political posture that is an issue. It’s also the substance of the case she is building. Valuation of assets is notoriously subjective, and the extent to which banks and insurers relied on those evaluations, and suffered as a result, has not yet come into focus. Mr. Trump will likely retort that his business interlocutors were sophisticated and possessed of independent judgment.

Cautionary notes for General James might be found in the facts that gave Mr. Bragg pause. One reason he dropped his investigation, the New York Times says, is that “Mr. Trump’s lenders had not lost money” on loans made to him or his company “but had in fact profited from them.” While the intricacies of the criminal code are opaque, to our eyes this shows signs of being a victimless crime, or even no crime at all. 

The Fifth Amendment dictates that no one “shall be compelled in any criminal case to be a witness against himself.” The Supreme Court, in McCarthy v. Arndstein, held in 1924 that it applied to civil cases as well, although in that procedure as opposed to its criminal cousin a court may instruct juries to draw an adverse inference from silence. Justice Louis Brandeis believed that in such settings “silence is often evidence of the most persuasive character.” 

We are struck by a tweet from the lead impeachment counsel and now congressional candidate, Daniel Goldman, who opined “you don’t take the Fifth if you didn’t do anything wrong.” What an obnoxious thing for any lawyer to say. Surely Mr. Goldman, a longtime prosecutor, knows that the Supreme Court — acting per curiam, no less — has held that “a witness may have a reasonable fear of prosecution and yet be innocent of any wrongdoing.” 

The legal noise around President Trump is amplifying. Mar-a-Lago was raided. White House Counsel Pasquale “Pat” Cipollone was subpoenaed. In taking the Fifth, Mr. Trump asserts an ancient right with roots in the torture chambers of the medieval age, when confessions were extracted on the rack. General James isn’t a medieval figure, but Mr. Trump is not guilty for asserting this right during his time of trial.