((a)) ** General authority** Under such regulations as the Secretary of State may prescribe, special agents of the Department of State and the Foreign Service may—
((1)) conduct investigations concerning—
((A)) illegal passport or visa issuance or use;
((B)) identity theft or document fraud affecting or relating to the programs, functions, or authorities of the Department of State;
((C)) transnational violations of chapter 77 of title 18 in which any part of the offense conduct occurred outside the United States or involved one or more foreign nationals; or
((D)) Federal offenses committed within the special maritime and territorial jurisdiction of the United States (as defined in ), except as such jurisdiction relates to the premises of United States military missions and related residences;
((2)) obtain and execute search and arrest warrants, as well as obtain and serve subpoenas and summonses issued under the authority of the United States;
((3)) protect and perform protective functions directly related to maintaining the security and safety of—
((A)) heads of a foreign state, official representatives of a foreign government, and other distinguished visitors to the United States, while in the United States;
((B)) the Secretary of State, Deputy Secretary of State, and official representatives of the United States Government, in the United States or abroad;
((C)) members of the immediate family of persons described in subparagraph (A) or (B);
((D)) foreign missions (as defined in section 4302(a)(4) of this title) and international organizations (as defined in ), within the United States;
((E)) a departing Secretary of State for a period of up to 180 days after the date of termination of that individual’s incumbency as Secretary of State, on the basis of a threat assessment; and
((F)) an individual who has been designated by the President or President-elect to serve as Secretary of State, prior to that individual’s appointment.
((4)) if designated by the Secretary and qualified, under regulations approved by the Attorney General, for the use of firearms, carry firearms for the purpose of performing the duties authorized by this section; and
((5)) make arrests without warrant for any offense against the United States committed in their presence, or for any felony cognizable under the laws of the United States if they have reasonable grounds to believe that the person to be arrested has committed or is committing such felony.
((b)) ** Agreements with Attorney General and Secretary of the Treasury and firearms regulations**
((1)) ** Agreement with Attorney General** The authority conferred by paragraphs (1) and (4) of subsection (a) shall be exercised subject to an agreement between the Secretary and the Attorney General.
((2)) ** Agreement with Attorney General and Secretary of the Treasury** The authority conferred by paragraphs (2) and (5) of subsection (a) shall be exercised subject to an agreement among the Secretary, the Attorney General, and the Secretary of the Treasury.
((3)) ** Firearms regulations** The Secretary of State shall prescribe regulations, which shall be approved by the Attorney General, with respect to the carrying and use of firearms by special agents under this section.
((c)) ** Secret Service not affected** Nothing in subsection (a)(3) shall be construed to preclude or limit in any way the authority of the United States Secret Service to provide protective services pursuant to section 3056 or 3056A of title 18 at a level commensurate with protective requirements as determined by the United States Secret Service. The Secretary of State, the Attorney General, and the Secretary of the Treasury shall enter into an interagency agreement with respect to their law enforcement functions.