PORTLAND, Ore. >> It has been nearly a decade since the terrorist attacks of 2001 and nearly a decade since this liberal city first established its reluctance to assist in many of the wide-ranging federal terrorism investigations that have followed.

No, it told Attorney General John Ashcroft in the fall of 2001, its police officers would not join federal efforts to interview thousands of Middle Eastern men. No, it said again in 2005, when it became the first city to stop participating in the Joint Terrorism Task Force, which the Department of Justice operates in cities across the country to unite federal, state and local law enforcement authorities.

And then, on Thanksgiving weekend last year, federal authorities arrested Mohamed Osman Mohamud, a Somali-born teenager they accused of trying to detonate a bomb at a Christmas tree-lighting ceremony attended by thousands of people. The investigation had been under way for many months, but the Portland police were consulted only near the end, largely to help with logistics of a sting operation. Mayor Sam Adams was unaware until after the arrest.

“It showed the challenges we face and the fact that the 2005 resolution, while well intentioned, wasn’t meeting the needs of collaboration between local and federal law enforcement,” Chief Michael Reese of the Portland police said in an interview. “You’re going to be an afterthought, like we were in that investigation.”

Now, after five months of public debate and rewritten drafts — and as Mohamud’s case moves slowly along — city leaders last week approved what one City Council member called a “very Portland” compromise to rejoin the task force.

“Be it resolved, that it is the policy of the city simultaneously to help prevent and investigate acts of terrorism, protect civil rights and civil liberties under United States and Oregon Law, and promote Portland as an open and inclusive community,” reads part of the preamble to the agreement.

The agreement goes on to emphasize that local officers will be guided by state law “in situations where the statutory or common law of Oregon is more restrictive of law enforcement than comparable federal law.” It also advises individual officers working with the task force to consult with the city attorney “whenever the officer has any question about the application of Oregon law.”

Under Oregon law, law enforcement agencies cannot collect information about a person’s political, religious or social views or group involvement “unless such information directly relates to an investigation of criminal activities, and there are reasonable grounds to suspect the subject of the information is or may be involved in criminal conduct.”

The upshot, Reese said, is that his department will soon be able to participate in longstanding regular briefings that already include the FBI, the State Police, county sheriff’s deputies, port authority officials and others. He will be allowed to apply for top-secret government clearance, and Adams, who is also the police commissioner, will be able to have secret clearance.

“A month from now, if we’re able to be there at the table and assign officers where it’s appropriate, I would be very happy,” Reese said.

The agreement passed unanimously among the city’s five commissioners, though many residents spoke against it. Some said it would stir more fear among Muslims already wary of federal agents. Some said officers would abuse the agreement.

“How do you spell oppression? J.T.T.F!” a small group of opponents chanted on the sidewalk outside City Hall during the debate, in easy earshot of Council members. “How do you spell police state? J.T.T.F!”

Some critics said the agreement was so nuanced that it was difficult to understand. “I don’t know if we are or if we’re not” joining the task force, Brandon Mayfield told Council members.

Mayfield, a lawyer, has experience in terrorism investigations that go wrong. In 2004, he was arrested after the FBI mistakenly said his fingerprints matched one found on a plastic bag containing detonator caps found at the scene of terrorist bombings in Madrid the same year. He eventually received a $2 million settlement and an apology from the federal government.

Mayfield said in an interview that he opposed the agreement but that he was pleased that “at least they are thinking of civil rights.”

“They don’t want to be deemed as being soft on security, but at the same time they are putting in all these precautions,” he said. “It shows they are listening to the citizens of this city.”

Much has happened in the decade since Portland first resisted. The mayor and the police chief are new. The lead FBI agent in Portland is new, as is the U.S. attorney here, Dwight C. Holton. The administration in Washington is also new.

“They were uncomfortable with some of the tactics in the war on terror,” said Holton. “They were uncomfortable with some of the politics of it, the national politics. Those folks are all gone now.”

Jeffrey L. Rogers, who was the city attorney in 2001 when Portland pushed back against Ashcroft, was among several people struck by the fact that the American Civil Liberties Union has given cautious support to the new agreement.

“It was harder to look for this kind of middle ground because the positions were so hardened,” Rogers said, recalling earlier debates. “Just on its face, that’s pretty impressive, to have all of those people agreeing.”