RSA 637:9 Unauthorized Use of Propelled Vehicle or Rented Property.

I. A person is guilty of theft if:
(a) Having custody of a propelled vehicle pursuant to an agreement between himself or another and the owner thereof whereby the actor or another is to perform for compensation a specific service for the owner involving the maintenance, repair or use of such vehicle, he intentionally uses or operates the same, without the consent of the owner, for his own purposes in a manner constituting a gross deviation from the agreed purpose; or
(b) Having custody of a propelled vehicle pursuant to a rental or lease agreement with the owner thereof whereby such vehicle is to be returned to the owner at a specified time and place, he abandons the vehicle or willfully refuses or neglects to redeliver it to the owner in such manner as he may have agree