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49 U.S. Code § 114 - Transportation Security Administration

(d) Functions.—The Under Secretary shall be responsible for security in all modes of transportation, including—
(1) carrying out chapter 449, relating to civil aviation security, and related research and development activities; and

(2) security responsibilities over other modes of transportation that are exercised by the Department of Transportation.

(e) Screening Operations.—The Under Secretary shall—
(1) be responsible for day-to-day Federal security screening operations for passenger air transportation and intrastate air transportation under sections 44901 and 44935;

(2) develop standards for the hiring and retention of security screening personnel;

(3) train and test security screening personnel; and

(4) be responsible for hiring and training personnel to provide security screening at all airports in the United States where screening is required under section 44901, in consultation with the Secretary of Transportation and the heads of other appropriate Federal agencies and departments.

(f) Additional Duties and Powers.—In addition to carrying out the functions specified in subsections (d) and (e), the Under Secretary shall—
(1) receive, assess, and distribute intelligence information related to transportation security;

(2) assess threats to transportation;

(3) develop policies, strategies, and plans for dealing with threats to transportation security;

(4) make other plans related to transportation security, including coordinating countermeasures with appropriate departments, agencies, and instrumentalities of the United States Government;

(5) serve as the primary liaison for transportation security to the intelligence and law enforcement communities;

(6) on a day-to-day basis, manage and provide operational guidance to the field security resources of the Administration, including Federal Security Managers as provided by section 44933;

(7) enforce security-related regulations and requirements;

(8) identify and undertake research and development activities necessary to enhance transportation security;

(9) inspect, maintain, and test security facilities, equipment, and systems;

(10) ensure the adequacy of security measures for the transportation of cargo;

(11) oversee the implementation, and ensure the adequacy, of security measures at airports and other transportation facilities;

(12) require background checks for airport security screening personnel, individuals with access to secure areas of airports, and other transportation security personnel;

(13) work in conjunction with the Administrator of the Federal Aviation Administration with respect to any actions or activities that may affect aviation safety or air carrier operations;

(14) work with the International Civil Aviation Organization and appropriate aeronautic authorities of foreign governments under section 44907 to address security concerns on passenger flights by foreign air carriers in foreign air transportation; and

(15) carry out such other duties, and exercise such other powers, relating to transportation security as the Under Secretary considers appropriate, to the extent authorized by law.