SECTION 1. IMMUNITY FOR REPORTS OF SUSPECTED TERRORIST ACTIVITY OR 
              SUSPICIOUS BEHAVIOR AND RESPONSE.

    (a) Immunity for Reports of Suspected Terrorist Activity or 
Suspicious Behavior.--
            (1) In general.--Any person, who, in good faith and based 
        on objectively reasonable suspicion, makes, or causes to be 
        made, a voluntary report based of covered activity to an 
        authorized official shall be immune from civil liability under 
        any Federal, State, or local law for such report.
            (2) False reports.--Paragraph (1) shall not apply to any 
        report that the person knew to be false or was made with 
        reckless disregard for the truth at the time that person made 
        the report.
    (b) Immunity for Response.--
            (1) In general.--
                    (A) Immunity.--Any authorized official who 
                observes, or receives a report of, covered activity and 
                takes reasonable action in good faith to respond to 
                such activity shall have qualified immunity from civil 
                liability for such action, consistent with applicable 
                law in the relevant jurisdiction.
                    (B) Additional immunity.--An authorized official 
                described in subsection (d)(1)(A) not entitled to 
                assert the defense of qualified immunity shall be 
                immune from civil liability under Federal, State, and 
                local law if such authorized official takes reasonable 
                action, in good faith, to respond to the reported 
                activity.
            (2) Savings clause.--Nothing in this subsection shall--
                    (A) affect the ability of any authorized official 
                to assert any defense, privilege, or immunity that 
                would otherwise be available; and
                    (B) be construed as affecting any such defense.
    (c) Attorney Fees and Costs.--Any person or authorized official 
found to be immune from civil liability under this section shall be 
entitled to recover from the plaintiff all reasonable costs and 
attorney fees.
    (d) Definitions.--In this section:
            (1) Authorized official.--The term ``authorized official'' 
        means--
                    (A) any employee or agent of a passenger 
                transportation system or other person with 
                responsibilities relating to the security of such 
                systems;
                    (B) any officer, employee, or agent of the 
                Department of Homeland Security, the Department of 
                Transportation, or the Department of Justice with 
                responsibilities relating to the security of passenger 
                transportation systems; or
                    (C) any Federal, State, or local law enforcement 
                officer.
            (2) Covered activity.--The term ``covered activity'' means 
        any suspicious transaction, activity, or occurrence that 
        involves, or is directed against, a passenger transportation 
        system or vehicle or its passengers indicating that an 
        individual may be engaging, or preparing to engage, in a 
        violation of law relating to--
                    (A) a threat to a passenger transportation system 
                or passenger safety or security; or
                    (B) an act of terrorism (as that term is defined in 
                section 3077 of title 18, United States Code).
            (3) Passenger transportation.--The term ``passenger 
        transportation'' means--
                    (A) public transportation, as defined in section 
                5302 of title 49, United States Code;
                    (B) over-the-road bus transportation and school bus 
                transportation;
                    (C) intercity passenger rail transportation as 
                defined in section 24102 of title 49, United States 
                Code;
                    (D) the transportation of passenger vessel as 
                defined in section 2101 of title 46, United States 
                Code;
                    (E) other regularly scheduled waterborne 
                transportation service of passengers by vessel of at 
                least 20 gross tons; and
                    (F) air transportation, as defined in section 40102 
                of title 49, United States Code, of passengers.
            (4) Passenger transportation system.--The term ``passenger 
        transportation system'' means an entity or entities organized 
        to provide passenger transportation using vehicles, including 
        the infrastructure used to provide such transportation.
            (5) Vehicle.--The term ``vehicle'' has the meaning given to 
        that term in section 1992(16) of title 18, United States Code.
            (6) Effective date.--This section shall take effect 
        immediately upon the date of enactment of this Act, and shall 
        apply to all activities and claims occurring on or after such 
        date.
Output: Grants immunity from civil liability to: (1) persons who, in good faith and based on an objectively reasonable suspicion, report suspicious activity involving or directed against a passenger transportation system, a threat to such system or to passenger safety or security, or an act of terrorism; and (2) passenger transportation security system employees or agents and other federal employees with transportation security responsibilities who take reasonable actions, in good faith, to respond to reported threats.