One of America’s most prominent jurists criticized acting-Attorney General Sally Yates, calling her refusal to defend President Trump’s recent executive order suspending immigration by refugees a “political decision” and a “serious mistake”.

Yates was dismissed Monday night after she instructed Justice Department officials not to defend last Friday’s executive order temporarily suspending the entry of asylum seekers via the US refugee resettlement program, and a ban on entry to citizens of seven predominantly Muslim countries flagged as terrorism hotspots.

Appearing on CNN Monday night, Alan Dershowitz hit Yates over her decision, and slammed the rush to judgment against the executive order.

"Sally Yates is a terrific public servant, but I think she's made a serious mistake here,” said Dershowitz. “This is 'hold-over heroism'. It's so easy to be a heroine when you're not appointed by this president and when you're on the other side. She made a serious mistake.”

While many critics of the ban, including Yates, claimed it violates the Constitution, Dershowitz counseled against sweeping generalizations, saying the issue was “very complicated”.

“I think what she [Yates] should have done is made a nuanced analysis of what parts of the order are constitutional, what parts are in violation of the statute, what parts are perfectly lawful. There's an enormous distinction between green card holders on the one hand, people who are in the country and have to be thrown out on the second hand, and people who are simply applying to get visas.”

Dershowitz, himself a Democrat who backed Trump’s 2016 election opponent, Hillary Clinton, noted his own opposition to the executive order as a matter of policy, even while rejecting suggestions it violates the Constitution’s ban on religious tests.

“There is also a distinction between what’s constitutional, what’s statutorily prohibited, what’s bad policy. This is very bad policy, but that’s lawful. And I think by lumping all of them together, she has made a political decision, rather than a legal one."

"These are very complicated legal issues and people shouldn't jump into them,” Dershowitz added.

"We have a hobby in this country; if you don't like something, you assume it's unconstitutional. Even my colleague, Elizabeth Warren, pointed to a part of the constitution that says 'No religious test shall ever be required'. But she didn't read the second part of it - 'for holding of office under the United States government'. It has nothing to do with visas."

Speaking just prior to the announcement of Yates’ removal from the Justice Department, Dershowitz advised President Trump not to fire her prior to the confirmation of Attorney General-designate Jeff Sessions.

"That would be a mistake also,” said Dershowitz.

"Just ignore her and say 'We're going to have the court appoint somebody who will defend the president's actions. The president has the right to have his actions defended."