Using the federal Freedom of Information Act and Maine's Right to Know Law, the organization is seeking to discover the nature of the stops and to investigate potential violations of the Fourth Amendment of the U.S. Constitution.

The Fourth Amendment protects people from unreasonable searches and seizures.

"None of us want to live in a checkpoint society, where we need government approval to run errands or take trips," Shenna Bellows, MCLU executive director, said in a press release issued Monday. "This seems like another example of government harassment of law-abiding Americans who aren't suspected of committing any crime."

Efforts on Monday to reach the public affairs office for the Houlton sector of the U.S. Border Patrol for reaction to the MCLU's efforts were unsuccessful.

Last year, a spokesman for the Border Patrol said the primary reason for the stops was potential terrorist threats, but that none had been uncovered.

The U.S. Supreme Court has held that law enforcement may engage in suspicionless searches at the border itself. The Border Patrol has interpreted that to mean it may stop motorists anywhere at anytime within 100 miles of the border.The MCLU is questioning whether suspicionless checkpoints near Old Town are a good use of government time and resources.

"What part of Maine doesn't lie within one hundred miles of the Canadian or a coastal border?" MCLU staff attorney Zachary Heiden asked in the press release. "By this definition, border patrol [agents] can stop anyone anytime anywhere in Maine for no good reason. We all want the police to catch people who break the law, but none of us wants to live in a police state."

The complaints already received included one from three youths detained for almost an hour and repeatedly interrogated as to whether they might have any drugs, which they did not; and an MCLU volunteer lawyer returning from a fishing trip with her boyfriend.

In conjunction with the investigation, the MCLU has launched a special Web site to collect information about those who were stopped last year and in April at the Old Town checkpoint.

The MCLU has requested that the government turn over copies of its policies and practices governing the operation of the Old Town checkpoint, as well as information about exactly who has been stopped and searched.

"We're asking the Border Patrol to produce justification for what seems to be virtually unchecked authority," Heiden said. "While individually these intrusions may seem harmless, over time we are chipping away at people's right to be left alone."

A federal judge in Bangor has expressed similar concerns.

U.S. Magistrate Judge Margaret Kravchuk earlier this year recommended that evidence obtained at a similar stop in the same location be suppressed.

"... [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."

Her decision is subject to review by U.S. District Judge John Woodcock.

A hearing is scheduled on the matter for July.