OLD TOWN (AP) – A federal magistrate judge has raised questions about the U.S. Border Patrol’s use of a checkpoint on Interstate 95 in an effort to crack down on illegal immigrants.

The checkpoint, similar to others used in the past, began April 2 and continues through Monday at various hours of the day and night. Although the primary target is illegal aliens, agents also are on the lookout for terrorists, weapons and drugs.

Border Patrol agents have set up their checkpoint in the southbound lane in a weigh station north of Old Town and are stopping every vehicle, checking to see if the motorists are citizens or aliens with the necessary credentials, said Matt Zetts, deputy chief patrol agent for the Houlton sector of the Border Patrol.

In many cases, he said, people are sent off in a matter of seconds, although some are sent to the weigh station for further questioning. “It’s done as expeditiously as possible,” the agent said.

The constitutionality of the checkpoints was tested when a Canadian motorist asked U.S. Magistrate Judge Margaret Kravchuk to suppress as evidence 140 pounds of marijuana allegedly seized from his minivan during a similar stop last September.

Joshua Gabriel, 29, of Ontario, was charged with possession of marijuana with intent to distribute and faces up to 20 years in federal prison if convicted.

“…(A)lthough I recognize that the intrusion upon an individual’s right to travel the highways without interruption is minimal,” Kravchuk wrote in her opinion, “the government simply has not demonstrated that its operation of the Old Town checkpoint appreciably advances any legitimate public interest.”

Kravchuk also concluded that “the traveling public ought not be asked to endure checkpoint stops” so close to Bangor unless the government could “demonstrate in some fashion that the public interest sought to be advanced is, in fact, advanced to some degree.”

The charges against Gabriel would likely be dropped if U.S. District Judge John Woodcock upholds Kravchuk’s recommendation that the evidence against Gabriel be suppressed.

Authorities chose the weigh station above Old Town because many northern Maine roads converge on the interstate and if illegal aliens have bypassed or gotten through the borders, they could be detected in Old Town.

“Basically anything coming from northern Maine can be checked north of Old Town,” Zetts said.

The Maine Civil Liberties Union says it has received complaints about the checkpoints.