49 C.F.R. § 1542.215 : Transportation — OTHER REGULATIONS RELATING TO TRANSPORTATION — TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY — CIVIL AVIATION SECURITY — AIRPORT SECURITY — OPERATIONS — Law enforcement support

(a) In accordance with §1542.217, each airport operator required to have a security program under §1542.103(a) or (b) must provide:
(1) Law enforcement personnel in the number and manner adequate to support its security program.
(2) Uniformed law enforcement personnel in the number and manner adequate to support each system for screening persons and accessible property required under part 1544 or 1546 of this chapter, except to the extent that TSA provides Federal law enforcement support for the system.
(b) Each airport required to have a security program under §1542.103(c) must ensure that:
(1) Law enforcement personnel are available and committed to respond to an incident in support of a civil aviation security program when requested by an aircraft operator or foreign air carrier that has a security program under part 1544 or 1546 of this chapter.
(2) The procedures by which to request law enforcement support are provided to each aircraft operator or foreign air carrier that has a security program under part 1544 or 1546 of this chapter.

49 C.F.R. § 1542.215