The Supreme Court of New Hampshire stated that the validity of a sobriety checkpoint depends upon two factors:
(1) whether it is more effective at advancing the public interest than other, less intrusive means; and
(2) whether its value outweighs the degree of intrusion it involves. (State of N.H. v. Hunt, 2007)

The Court identified two separate public interests that might be advanced by sobriety checkpoints: detection of drunk drivers and deterrence of drunk driving. Regarding the deterrent effect of sobriety checkpoints, the Court found that publicity about roadblocks is the chief means of deterrence and that the deterrent value of the checkpoint program in that case was lessened, and its potential for surprise was increased, by a complete lack of advance publicity. Although The Supreme Court of New Hampshire held that sobriety checkpoints can violate Part I, Article 19 of the State Constitution, they did not hold that every sobriety checkpoint constitutes a per se violation of Article 19. Meaning a properly designed and implemented program of sobriety checkpoints could meet constitutional requirements.

The New Hampshire Attorney General's office produced and disseminated, as chapter XXV of its 1993 Law Enforcement Manual, a set of guidelines for sobriety checkpoints. Among other things, those guidelines call for the achievement of a maximum deterrent effect through aggressive public information efforts.

The Attorney General's office deems the chief advantage that sobriety checkpoints enjoy over more conventional DWI enforcement methods lies in their deterrent effect. Although information about a sobriety checkpoint program may be expected, over time, to pass by word of mouth, it is only through an aggressive program of advance publicity that the deterrent potential of a sobriety checkpoint program can be fully realized. Virtually every court which has addressed the sobriety checkpoint issue has suggested that advance publicity is an extremely important factor. Public awareness maximizes the deterrent value of the sobriety checkpoint, and minimizes fear and apprehension on the part of the motoring public. In 2007, The Supreme Court of New Hampshire found publication by the Portsmouth Police Department in the Fosters Newspaper was adequate publication.

Law enforcement agencies should make full use of the various media resources available. Press conferences, press releases, radio and television coverage, posters and flyers should all be considered as means of increasing public awareness of the existence of sobriety checkpoints. Only through an aggressive public information campaign can the true deterrent value of sobriety checkpoints be realized. Advance notice through media sources, coupled with appropriate warning signs at the individual checkpoint site, and substantially reduces apprehension occasioned by the sobriety checkpoint. In 2007, the Court found less than 24 hours advance notice was a sufficient amount of time to not find a Constitutional violation.

The legislature enacted RSA 265:1-a (2004), which provides:

• Sobriety Checkpoints. Notwithstanding any provision of law to the contrary, no law enforcement officer or agency shall establish or conduct sobriety checkpoints for the purposes of enforcing the criminal laws of this state, unless such law enforcement officer or agency petitions the superior court and the court issues an order authorizing the sobriety checkpoint after determining that the sobriety checkpoint is warranted and the proposed method of stopping vehicles satisfies constitutional guarantees.
• Sobriety checkpoints can't be used as a backdoor method to find other types of criminal violations. They must be published in advance by at least one newspaper. After 2007, the law enforcement agencies of New Hampshire were given more freedom to conduct sobriety checkpoints by the recent Supreme Court decision.