N.H. Rev. Stat. § 266-A:22
Upon complaint in writing by any person, organization, or body politic, or upon its own initiative, the department may investigate whether any motor carrier has failed to comply with any provision of this chapter, or with any requirement established pursuant thereto. If the department, after notice and hearing, finds upon any such investigation that the motor carrier has failed to comply with any such provision or requirement, the department may issue an appropriate order to compel the carrier to comply therewith. Whenever the department is of the opinion that any complaint does not state reasonable grounds for investigation and action on its part, it may dismiss such complaint.
RSA 266-A:22
1941, 224:22. RL 304:22. RSA 376:22. 1985, 402:6, I(e)(7).