In coordination with the Department of Public Safety and the Department of Transportation and Public Facilities, the department may

(1) formulate and execute plans and regulations for the control of traffic for the rapid and safe movement of evacuation over public highways and streets of people, troops, or vehicles and materials for homeland security and civil defense; and

(2) establish and operate checkpoints along private or public roadways serving critical property or facilities in the state, at the direction of the governor when the governor determines that a sufficiently high threat of enemy or terrorist attack exists to warrant the action; the checkpoints established under this paragraph may be in conjunction with closure of the roadway under AS 19.10.100; operation of a checkpoint shall include the posting of checkpoint signs in a manner that provides advance notice of the checkpoint so that persons are afforded a reasonable opportunity to turn around without passing through the checkpoint; operation of a checkpoint shall be limited to enforcement of the roadway closure or reasonable inspection of persons and vehicles passing through the checkpoint for weapons, explosives, chemicals, biological or biochemical agents, or other instruments capable of causing widespread severe injury to persons or property; however, at a checkpoint authorized under this paragraph, a person is entitled to retain possession of an amount of deadly weapons or defensive weapons that is reasonably justifiable for the person's lawful use, so long as those weapons are not prohibited weapons; in this paragraph, “deadly weapon” and “defensive weapon” have the meanings given in AS 11.81.900(b), and “prohibited weapon” has the meaning given in AS 11.61.200.