“Judges as persons, or courts, as institutions, are entitled to no greater immunity from criticism than other persons or institutions. There have sometimes been martinets upon the bench … who have used the paraphernalia of power in support of what they called their dignity. Therefore, judges must be kept mindful of their limitations, and of their ultimate public responsibility by a vigorous stream of criticism expressed with candor, however blunt.” We should not “protect the court as a mystical entity, or the judges … as anointed priests set apart from the community and spared the criticism to which in a democracy other public servants are exposed.”

Who said this? a) Donald Trump; b) Steve Bannon; c) George Wallace; d) Felix Frankfurter; e) Hitler.

If you know how questions like this work, you may have correctly guessed that the answer is “d.” But based upon the acute consternation of the liberal and legal establishments this week over President Trump’s “assault on judicial independence,” it would be understandable if you’d chosen a or b, or even c or e.

This latest fit of high dudgeon about Trump has been provoked by his tweets about the “so-called judge” who stayed his executive order temporarily suspending travel and immigration from seven countries, and his criticism of the appellate panel reviewing that stay. His language was classic unrefined Trump: the judge’s decision was “ridiculous” and “put our country in such peril. If something happens blame him and court system. People pouring in. Bad!”

And in a speech to police chiefs he vented his exasperation that “a bad high school student would understand” the seemingly plain language of one of the relevant immigration statutes, which on its face appears to give him the power to issue the executive order, but the “political” judges hearing the appeal of the case talked in legal mumbo-jumbo that had “nothing to do with” the statute.

To the head of the American Bar Association these statements were not merely coarse and perhaps simplistic, but “attacks on our Constitution” that threatened “the rule of law.” Another commentator branded them a “bone-chilling” attempt to “delegitimize the judiciary” by undermining its independence and the constitutional separation of powers. Even Trump’s Supreme Court nominee Neil Gorsuch, in a private conversation with U.S. Sen. Richard Blumenthal (D-Conn.) that the lawmaker immediately made public, termed the president’s remarks “demoralizing” and “disheartening.” (If this was an attempt by Gorsuch to mollify Blumenthal and other Democrats it wasn’t successful: Blumenthal still blasted him for failing to condemn Trump publicly, and a spokesman for Senate Minority Leader Chuck Schumer dismissed Gorsuch’s private criticism of the President as “milquetoast.”)

The dispute recalls similar controversies where liberal and bar groups accused former New York City mayors Rudy Giuliani and Ed Koch of threatening judicial independence by criticizing judges who issued lenient criminal justice rulings. Koch, an avowed “liberal with common sense,” used language strikingly similar to Trump’s, denouncing court decisions as “bizarre” and “ridiculous.”

The outrage at Koch and Giuliani was unjustified, as is the outrage at Trump now. While Trump’s language (like Koch’s) may not be to the taste of appellate lawyers, there is nothing illegitimate about it. In fact, as the quotation from Justice Frankfurter above suggests, the courts have held that even harsh and distasteful attacks on judges are a valid and important exercise of first amendment rights.

While some Trump critics like New York Mayor Bill de Blasio accuse him of “defying” the courts with his tweets and bluster, he has done no such thing. He has not proclaimed, in the infamous but apocryphal words attributed to Andrew Jackson, that the judge “has made his decision, now let him enforce it.” Rather, he has obeyed the judge’s order suspending the travel moratorium, and the appellate ruling upholding that order—as he must unless and until it is reversed or lifted. This is what separation of powers and judicial independence demand, but it is all that they demand.

Many liberals and lawyers go to the other unconstitutional extreme from defiance, encroaching on free speech rather than separation of powers, when they suggest that respect for judicial independence requires silence as well as obedience, and that it is inappropriate for members of the other branches, or ordinary citizens, to criticize judges. But judges are no more above the law than are presidents, and just as presidents are subject to constitutional restraints on their powers, so must judges be subject to the bedrock constitutional right of dissent.

The courts themselves have actually agreed—including the famously liberal Ninth Circuit that Trump criticized and that upheld the stay of his executive order. In the leading 1941 case of Bridges v. California, the Supreme Court reversed contempt convictions of a labor leader and a newspaper for critical comments about pending cases. The opinion by Justice Hugo Black squarely rejected the notion that criticism of judges, even when not in “perfect good taste,” delegitimizes the judiciary, and that this concern trumps the public interest in robust free speech:

The assumption that respect for the judiciary can be won by shielding judges from published criticism wrongly appraises the character of American public opinion. For it is a prized American privilege to speak one’s mind, although not always with perfect good taste, on all public institutions. And an enforced silence, however limited, solely in the name of preserving the dignity of the bench would probably engender resentment, suspicion, and contempt much more than it would enhance respect.”

The quote from Justice Frankfurter at the top comes from his dissenting opinion in Bridges, which, while disagreeing on the particulars of the case, stated this principle even more forcefully. A half century later the Ninth Circuit, in an opinion by the respected Judge Alex Kozinski, quoted Bridges in reversing the suspension of a lawyer who had called a judge a dishonest, ignorant, anti-Semitic buffoon who drank on the bench.

It has become all the more crucial since Bridges to allow even the most intemperate speech criticizing judges, as the judiciary has assumed so much power over many of the most important and contentious social and political issues. At the same time, the legal and judicial communities have moved sharply to the left on these issues, often reaching decisions that seem to ordinary citizens to be, as Koch put it, “bizarre,” arrived at by a legalistic hocus-pocus that seems, as Trump put it, to have “nothing to do with” the actual law.

Trump, like Koch before him, is rightly giving voice (in the same blunt outer-borough style) to the public dismay with this.