The American Civil Liberties Union Wednesday that the slapped on former President in his federal interference case violates the U.S. Constitution.

The ACLU, a frequent and vocal critic of Trump that his criminal indictment in the federal case in Washington, D.C., said that the restrictions placed on his speech run afoul of the First Amendment.

"No modern-day president did more damage to civil liberties and civil rights than President Trump," said the group's executive director, Anthony Romero, in a .

"But if we allow his free speech rights to be abridged, we know that other unpopular voices — even ones we agree with — will also be silenced," Romero said.

"As much as we disagreed with Donald Trump's policies, everyone is entitled to the same First Amendment protection against gag orders that are too broad and too vague," he said.

U.S. District Judge Tanya Chutkan imposed a partial gag order on Trump in mid-October, after special counsel Jack Smith's prosecutors argued that the ex-president's bellicose statements about the case risked prejudicing the trial.

Trump has repeatedly fulminated against the judge, the prosecutors, the jury pool and potential witnesses in the case, which accuses him of illegally conspiring to overturn his 2020 election loss to President . Trump has pleaded not guilty.

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Chutkan's order bars Trump and other parties in the case from making public statements about Smith, the defense counsel, members of the court or any of their staffers.

They are also prohibited from targeting "any reasonably foreseeable witness or the substance of their testimony."

In an 18-page court filing, the ACLU argued that Chutkan's order is too vague, too broad and not sufficiently justified.

Trump has made many "patently false" statements that have "caused great harm to countless individuals," the group wrote. But he nevertheless "retains a First Amendment right to speak, and the rest of us retain a right to hear what he has to say."

Any restraint on Trump's speech must be "precisely defined and narrowly tailored," the ACLU wrote, arguing that Chutkan's order "fails that test."

For example, Chutkan's prohibition on making public statements that "target" certain individuals is "unconstitutionally vague," the ACLU wrote.

"Reading the order, Defendant cannot possibly know what he is permitted to say, and what he is not," the group wrote.

Chutkan's three-page order on Oct. 17 is "overbroad and underexplained," the ACLU added.

The group's filing in U.S. District Court in Washington, known as an amici curiae or "friend of the court" brief, urges Chutkan to reevaluate her order.

Trump has appealed Chutkan's gag order to the U.S. Court of Appeals for the District of Columbia Circuit.

Chutkan last week put her gag order on pause as she considers a request from Trump's attorneys for a stay pending the appeal.

Following that pause, Trump has resumed making public statements attacking Smith and others arguably covered by the order.

Trump was hit with a separate gag order by the judge presiding over his civil fraud trial in New York. That judge, Arthur Engoron of Manhattan Supreme Court, banned the parties from making public statements about his staff after Trump sent a Truth Social post attacking his law clerk.

Engoron last week found that Trump violated that gag order, fining him $5,000 and threatening more severe sanctions, including imprisonment, if the violations continue.

A lawyer for Trump did not immediately respond to a request for comment on the ACLU's filing.