The consent once removed doctrine allows a warrantless police entry into a home when consent to enter was previously granted to an undercover officer who observed contraband in plain view. If sued for a civil rights violation, the cops say they have immunity because the doctrine authorized their actions.

That's how the district court in Utah ruled in this case. But the 10th circuit reversed because the plaintiffs were trying to extend the doctrine from undercover officers to undercover informants. It was the snitch in this case who made the initial buy inside the home which then resulted in a warrantless search of the home after the seller's arrest. The seller-plaintiff sued the cops seeking damages for violating his civil rights through the unconstitutional search. He alleged the cops improperly supervised the warrantless search.

The [Tenth Circuit] concluded that petitioners could not reasonably have believed that their conduct was lawful because they knew that (1) they had no warrant; (2) respondent had not consented to their entry; and (3) his consent to the entry of an informant could not reasonably be interpreted to extend to them.

So now what? The consent once removed doctrine still is illegal in the Tenth Circuit, but it lost its back teeth because officers can't be sued if they violate it. (It keeps its front teeth -- the evidence would be excluded in the criminal case.)

Alito on precedent:

Revisiting precedent is particularly appropriate where, as here, a departure would not upset settled expectations, see, e.g., United States v. Gaudin, 515 U. S. 506, 521; the precedent consists of a rule that is judge-made and adopted to improve court operations, not a statute promulgated by Congress, see, e.g., State Oil Co. v. Khan, 522 U. S. 3, 20; and the precedent has “been questioned by Members of th[is] Court in later decisions, and [has] defied consistent application by the lower courts.”

I wonder what other Supreme Court rulings might this apply to.

It wasn't Alito's only anti-defense ruling of the day. He joined Chief Justice Roberts' dissent from the favorable crack-powder cocaine sentencing ruling in Spears v. United States (pdf) TChris writes about here. In its per curiam ruling, the Court held:

"[W]e now clarify that district courts are entitled to reject and vary categorically from the crack cocaine Guidelines based on a policy disagreement with those Guidelines. Here, the District Court’s choice of replacement ratio was based upon two well-reasoned decisions by other courts, which themselves reflected the Sentencing Commission’s expert judgment that a 20:1 ratio would be appropriate in a mine-run case. "