In a rebuke to the Trump administration’s immigration enforcement policies, a New Hampshire court ruled last week that a Border Patrol checkpoint on an interstate highway last summer was “unconstitutional under both State and federal law.”

Don’t believe for a second the administration’s official response that this decision “does not affect the U.S. Border Patrol’s federal authority to conduct immigration checkpoints.” All motorists’ constitutional rights got a huge boost from Judge Thomas Rappa’s refusal to give Trump’s deportation force a blank check to pretextually set up a drug checkpoint under the guise of immigration enforcement.

Why was this checkpoint unlawful?

Because federal customs and border agents used impermissible dog-sniff searches to go after drugs without a warrant and without any reasonable suspicion that a crime had been committed. After conducting these dog-sniff searches, CBP agents then turned over to the local police the resulting evidence for state drug prosecutions.

Hundreds, if not thousands, of individuals were searched and seized on Interstate 93 in August 2017, including 16 individuals who the ACLU of New Hampshire represented in court. On behalf of these 16, the ACLU-NH and co-counsel asked the state district court to suppress the small amount of drugs allegedly found during the checkpoint.

The court agreed to suppress the evidence and ruled that these searches violated the New Hampshire Constitution. While the U.S. Constitution may allow warrantless and suspicionless dog-sniff searches, the New Hampshire Constitution specifically forbids it. Nevertheless, state prosecutors brought charges in state court based on evidence that was illegally seized under state law.

The court explained that the “inadmissibility of the evidence does not change based on the fact that it was seized by federal officers and then handed over to the State.” According to the court, the New Hampshire Constitution had to apply because CBP and the local police “were working in collaboration with each other with the understanding that the [local police] would take possession of any drugs seized below the federal guidelines for prosecution in federal court and bring charges in this [state] court based on that evidence.”

Indeed, after the checkpoint, the local police chief boasted to the local press that CBP has “a lot more leeway” to conduct searches, noting that he himself could not subject drivers to a dog sniff without reasonable suspicion of a crime.

The court also ruled that the Woodstock checkpoint violated the Fourth Amendment. Federal law provides CBP with the authority to conduct temporary and limited immigration checkpoints within 100 air miles of any land or coastal border so long as there is a required nexus to a border crossing. Since the entire state sits within 100 miles of the Canadian border and the Atlantic Ocean, CBP asserts that it can set up immigration checkpoints across all of New Hampshire.

Under the Fourth Amendment, however, the United States Supreme Court has only authorized these interior checkpoints within the 100-mile zone, like the one in Woodstock, under limited circumstances for brief immigration inquiries. During these brief inquiries, all that is required of the vehicle’s occupants is “a response to a brief question or two and possibly the production of a document evidencing a right to be in the United States.” Border patrol agents cannot search the vehicles or occupants without probable cause, and the primary purpose of the checkpoint cannot be drug-related.

KNOW YOUR RIGHTS IN THE BORDER ZONE

The court concluded that this checkpoint violated these Fourth Amendment rules because the checkpoint’s primary purpose was drug interdiction, not immigration enforcement. As Judge Rappa explained, “it is patently clear that the primary purpose of [the local police] being present at the checkpoint in August [was] to accept the illegal drugs confiscated by the CBP searches in order to prosecute the defendants on state drug charges.” Indeed, Border Patrol often pretextually uses checkpoints to maximize drug seizures and arrests as part of the war on drugs.

Our concerns about this incident don’t end there.

We are also suspicious of the central role played in drug detection by Border Patrol canines. These dogs are often not adequately trained and certified and thus lead to frequent false alerts, which result in unjustified searches and detentions. The court was correctly suspicious of this too, noting that “there were numerous, ‘non-productive alerts,’ by the dogs at the [Woodstock] checkpoints which extended the duration of the stops … but resulted in no evidence of a crime being found.” Indeed, the court granted our motion to suppress as to seven defendants on an alternative ground that no evidence was presented regarding the Border Patrol canine’s training or certification.

This New Hampshire court decision, as one commentator noted, “serves as a crucial reminder that the agency can’t always use the pretext of illegal immigration to curtail civil liberties.” Here, CBP abused its federal authority, in collaboration with local police, to circumvent the constitutional rights of those traveling in New Hampshire.

So we sued. And we won.