Donald Trump Immigration Ban

President Donald Trump, center, with Vice President Mike Pence, left, and Defense Secretary James Mattis, right, watching, signs an executive action on extreme vetting at the Pentagon in Washington, Friday, Jan. 27, 2017.

(Susan Walsh/AP Photo)

U.S. District Judge Dan Polster

BRATENAHL, Ohio -- A longtime Cleveland federal judge hinted that President Donald Trump's recent attacks on the judges hearing challenges to his executive order on immigration were disheartening.

U.S. District Judge Dan Polster made the comments during a speech Wednesday night to the civil rights committee of Cleveland's Anti-Defamation League without mentioning Trump's name. He noted that comments like the ones that the new president made this week could be dangerous.

"This is serious business, because you start calling into question the legitimacy of someone, that undermines the whole system, all right?" Polster said in response to a question on whether he was worried about the judiciary's status under Trump.

Polster, an appointee of President Bill Clinton who has been on the bench since 1998, was invited to the meeting to share his recent experience as a visiting judge in Las Cruces, New Mexico near the U.S.-Mexico border.

Speaking in a penthouse in Bratenahl to a small group that included suburban mayors, attorneys and city officials, the judge chose his words carefully as he spoke for about 10 minutes on the subject, mindful of the position he holds and that reporters were in attendance.

He said a public office holder in one government branch who makes those types of comments "calls into question his or her own legitimacy."

"I think to say it publicly, that's his right," Polster told the crowd. "But it calls into question, and some might even say forfeits, his or her own legitimacy. So I'll leave it at that. It's an important question, but that's how I feel."

Trump harshly criticized Washington state federal Judge James Robert and a California federal appeals court. Robart, a George W. Bush appointee, placed a stay on the president's executive order on immigration from seven Muslim-majority countries last week. The appeals court heard arguments Tuesday on the executive order.

The appeals court challenged the administration's claim that the ban was motivated by terrorism fears but also questioned an attorney's argument that it unconstitutionally targeted Muslims.

Trump labeled Robart a "so-called judge" in a tweet over the weekend and referred to the ruling as "ridiculous." On Wednesday, he slammed the appeals court, telling a group of police chiefs that his immigration order was "done for the security of our nation."

He quoted from the portion of the immigration law that he said gave him the power to enact the ban, calling it "beautifully written" and saying "a bad high school student would understand this."

Criticism of Trump and his surrogates' comments has been fierce. Even Judge Neil Gorsuch, Trump's nominee for an open U.S. Supreme Court seat, called the president's comments "demoralizing and disheartening."

Polster said Wednesday that "I've said many times that the Constitution never sleeps and our branch is on it." He said he still feels the American system of government is the best in the world and was set up by the founding fathers because "they were fearful of a president who might want to be a king or dictator."

But he said all federal judges take their roles seriously and he doesn't see any of them backing down based on pressure from the executive branch.

"I don't believe there's a single federal judge who would be intimidated by anybody," Polster said. "We took an oath to support and defend the Constitution and it means a lot. And I think that oath means even more today."

Polster stressed to the group that he did not think it was improper for anybody to criticize a judge's actions.

But "when you call into question the legitimacy of a federal district court judge, that's a line that shouldn't be crossed," he said.

The Associated Press contributed to this report.