Yates said she was not "convinced" about the legality of Trump's decision to block travelers from Iraq, Iran, Syria, Yemen, Sudan, Libya and Somalia for 90 days; to suspend new refugee admissions; and to ban the acceptance of Syrian refugees indefinitely.
Her letter cited a sense of responsibility for both law and justice:
"My responsibility is to ensure that the position of the Department of Justice is not only legally defensible, but is informed by our best view of what the law is after consideration of all the facts. In addition, I am responsible for ensuring that the positions we take in court remain consistent with this institution's solemn obligation to always seek justice and stand for what is right. At present, I am not convinced that the defense of the Executive Order is consistent with these responsibilities nor am I convinced that the Executive Order is lawful.
"Consequently, for as long as I am the Acting Attorney General, the Department of Justice will not present arguments in defense of the Executive Order, unless and until I become convinced that it is appropriate to do so."
Justice lawyers had been in courts all over the country this past weekend on the opposing side of refugees and travelers, often making weak arguments and stating they didn't have enough information about the executive order and its legal underpinnings.
The Justice Department confirmed its Office of Legal Counsel had done a review of the order to determine whether it was "on its face, lawful, and properly drafted."
But the objections Yates raised in her bombshell letter pointed out the OLC review didn't consider statements "made by an administration or its surrogates...that may bear on the order's purpose."
That passage appeared to refer to comments by Rudy Giuliani, who told Fox News that Trump had wanted to impose a "Muslim ban" but wanted advisers to find a way to do it "legally." Immigrants rights advocates said Giuliani's remarks could offer them evidence to prove the administration had a "discriminatory purpose."
The order set off chaos — and protests — across the country as many people with valid visas and legal U.S. residents with green cards were denied entry and threatened with deportation. On Saturday night, federal Judge Ann Donnelly issued a stay on the deportations of valid visa holders.
Lee Gelernt, deputy director of the American Civil Liberties Union's Immigrants' Rights Project, said of the DOJ action: "This is a remarkable but welcome development and sends a powerful message that there's something very wrong with a Muslim ban."
As the news was breaking of the directive from Yates, Trump senior policy adviser Stephen Miller told MSNBC's Greta Van Susteren that Yates' decision was "a further demonstration of how politicized our legal system has become."
And inside the White House, Trump tweeted about Democratic obstruction of his nominees, "Now have an Obama AG." Less than two hours later, Yates was out of a job.
Her successor, Dana Boente, pledged to "defend and enforce the laws of our country to ensure that our people and our nation are protected."
It's very unusual for the Justice Department to refuse to defend a law or an executive order, though it isn't unprecedented. During the Obama administration, for example, top officials decided not to defend the Defense of Marriage Act that defined marriage as between one man and one woman. The Supreme Court eventually ruled in favor of same-sex marriage.
Trump could remove Yates, but there would be no one at the Justice Department who could sign Foreign Intelligence Surveillance Act warrants, which would leave a big gap in national security.
