At the same time, an immigration rights group in Seattle urged anyone contacted for questioning to be aware of their civil rights.
"There is no law that requires you to answer questions," Leah Iraheta, executive director of the Northwest Immigrant Rights Project, told the Seattle Times. "My advice is, that if they don't have a piece of paper that says they can talk to you, then to just say, 'I'm sorry, I can't talk' and just shut the door."
The Justice Department plans to talk to about 5,000 recent arrivals from various nations considered to be terrorism sponsors in the next 30 days and has asked local police departments to assist with the questioning; Portland is home to about 200 men on the list.
Assistant Police Chief Andrew Kirkland said Tuesday that his department would not take part due to the likelihood the questioning would clash with state law.
"You can't use personnel and equipment just to go out and randomly interview people solely on immigration," said Kirkland, who was filling in for the vacationing Chief Mark Kroeker.
Mayor Vera Katz called Kirkland's decision "a wise one."
"I do have a concern when we're asked to do something that violates state law," she told the Portland Oregonian.
It was not known Wednesday if the city would seek clarification of the law or would let Kirkland's decision stand.
Portland officials pointed out that state law prohibits police from questioning people unless they are suspected of a crime. The FBI, however, enjoys less restrictive standards.
David Fidanque, executive director of the American Civil Liberties Union of Oregon, testified before the Portland City Council on Oct. 27 about the possible legal conflict caused by city police acting as de facto federal agents in the growing effort to track down terrorists who may be lurking in the shadow within the United States.
"Even if the Portland officers will be subject to the greater restrictions of state law on their activities, information which they gather consistent with Oregon law that would periodically have to be purged from city files will remain with the FBI on a permanent basis," Fidanque testified. "FBI files are forever -- even if the subjects of those files turns out to be innocent of any wrongdoing."
There was no immediate comment on the Portland situation from Justice Department officials in Washington, although Michael Mosman, the U.S. attorney for Oregon, said Tuesday that the issue was "a tempest in a teapot."
"We are interviewing a number of people nationwide just to get more information," he told the Oregonian, comparing the questioning of the men on the list to police talking to bystanders at the scene of a traffic accident.