18 U.S.C. § 2236 — Searches without warrant

Whoever, being an officer, agent, or employee of the United States or any department^* or agency^* thereof, engaged in the enforcement of any law of the United States, searches any private dwelling used and occupied as such dwelling without a warrant directing such search, or maliciously and without reasonable cause searches any other building or property without a search warrant, shall be fined under this title for a first offense; and, for a subsequent offense, shall be fined under this title or imprisoned not more than one year, or both.

This section shall not apply to any person—

(a) serving a warrant of arrest; or

(b) arresting or attempting to arrest a person committing or attempting to commit an offense in his presence, or who has committed or is suspected on reasonable grounds of having committed a felony; or

(c) making a search at the request or invitation or with the consent of the occupant of the premises.