In November, just days after the American electorate gave Republicans strong majorities in both chambers of Congress, President Obama thumbed his nose at several million voters by issuing an executive order effectively granting amnesty to 5 million–plus immigrants residing in the United States illegally. That lawless action was, naturally, supported by Attorney General Eric Holder, whose primary contribution as head of the Department of Justice for six years has been to grant specious legal imprimatur to the president’s various usurpations of legislative power.

Loretta Lynch, U.S. attorney for the Eastern District of New York, nominated to be Mr. Holder’s replacement, has proven herself equally unfit for the office. That some Senate Republicans seem prepared to swiftly confirm her to office is an abnegation of their November mandate and, even more important, their constitutional duty.

In Senate confirmation hearings held this week, Ms. Lynch has evaded questions from Louisiana senator David Vitter about whether the amnesty order will actually be carried out on a “case-by-case basis,” as even the administration’s own lawyers say is required by law, and from Utah senator Mike Lee and Texas senator Ted Cruz about whether a future president could, under President Obama’s rationale of “prosecutorial discretion,” decline to enforce tax or labor or environmental laws. But among the things she has stated unequivocally is her belief that the president’s executive order is “legal and constitutional.” She even went further, telling Alabama senator Jeff Sessions that “the right and the obligation to work is one that’s shared by everyone in this country regardless of how they came here.” Such an assertion is both ahistorical and constitutionally insupportable. But it is the president’s own alarming view, and simply confirms that Ms. Lynch, like Eric Holder, would lend the Justice Department’s endorsement to the president’s lawlessness.