N.H. Rev. Stat. Ann. § 126-D:3

The commissioner, department of health and human services, or his designee, is hereby authorized to develop, participate in the development of, negotiate, enter into and execute one or more interstate compacts on behalf of this state with other states to implement the purposes set forth in this chapter. When so executed, and for so long as it shall remain in force, such a compact shall have the force and effect of law.