The memo is here.
Can ICE enter a home to make an arrest without a judicial warrant?
The standard view has been that administrative warrants cannot authorize home entry because they are executive-branch orders, and the executive cannot decide whether to give itself a warrant. Under Payton v. New York, the government needs an arrest warrant to enter a home, and Payton emphasizes a “judicial officer” inserting judgment “between the zealous officer and the citizen.” An immigration officer signing a Form I-205 is not a judicial officer.
Judge Wright’s reasoning in Kidd v. Mayorkas reflects this traditional view. It is especially compelling under the unitary executive theory, which treats all immigration officials as exercising the President’s executive power. Given Coolidge, Shadwick, and Payton’s focus on warrants as a judicial check on the executive, it seems implausible to say that the executive checking itself satisfies the Fourth Amendment—even when an I-205 follows an immigration judge’s removal order, which is still an executive-branch act.