N.H. Rev. Stat. Ann. § 236:31-b

Any person who fails, neglects, or refuses to pay the toll or charge for the use of any bridge, highway, or part thereof, or utilizes a toll lane that is equipped with a toll collection monitoring system without having an E-Z Pass transponder mounted on the vehicle, shall have an image taken of the vehicle registration plate and be subject to the provisions of RSA 236:31. When a full cash payment is made at the tollbooth, and the vehicle exits the toll booth, the image (i) shall not be retained for more than 3 seconds, after which it shall be irretrievably destroyed, and no record of the image or its destruction shall be kept; (ii) shall not be made available or disclosed to any individual, person, entity, or government or any component thereof; and (iii) shall not be subject to a subpoena or any administrative or court order.