The visitors are federal agents.
Opponents of Canadian oil say they've been contacted by FBI investigators in several states following their involvement in protests that delayed northbound shipments of equipment to Canada's oilsands.
A lawyer working with the protesters says he's personally aware of a dozen people having been contacted in the northwestern U.S. and says the actual number is probably higher.
Larry Hildes says it's been happening the last few months in Washington State, Oregon and Idaho. He says one person got a visit at work, after having already refused to answer questions.
"They appear to be interested in actions around the tarsands and the Keystone XL pipeline," Hildes said in an interview.
"It's always the same line: 'We're not doing criminal investigations, you're not accused of any crime. But we're trying to learn more about the movement.'"
He's advised activists not to talk — and they mostly haven't. That lack of communication has made it a little complicated to figure out what, exactly, the FBI is looking for.
The bureau hasn't offered too many clues.
One agent left his name, number, and the following message in a voicemail for Helen Yost of the group Wild Idaho Rising Tide: "I work with the FBI. Could you give me a call back — I would appreciate it."
Is anti-oilsands activity an actual focus of the FBI investigation, or is it merely incidental? The bureau won't say.
What it will say is that it only investigates potential crimes, not political movements.
"The FBI has the authority to conduct an investigation when it has reasonable grounds to believe that an individual has engaged in criminal activity or is planning to do so," said FBI spokeswoman Ayn Dietrich.
"This authority is based on the illegal activity, not on the individual's political views."
But activists say oilsands opposition appears to be the common thread among people being contacted. Police have been in touch with people from different groups, who in some cases don't agree on much, but one thing they share is mutual participation in the so-called megaload protests.
Those are the intermittent highway blockades set up the last few years to complicate the enormous, football-field-sized shipments of processing equipment up to the oilsands.
Yost said only two people from her group participated in that anti-oilsands action — and those are the people who've been contacted by the FBI. She has refused to co-operate.
The other person, Herb Goodwin, was visited at home by an FBI agent and a veteran detective from the local police force in Bellingham, Wash. He said the federal agent told him: "We're here to ask whether you'll answer some questions for us about Deep Green Resistance."
That group, DGR, calls itself a radical environmental movement that believes the biggest problem with the planet is human civilization itself. It proposes a shift back from agriculture to a hunter-gatherer horticultural lifestyle.
It also proposes a four-step program called decisive ecological warfare, a long-term plan calling for the sabotage and dismantling of planet-harming infrastructure.
The group has repeatedly stated that it wouldn't participate itself in any such actions. But Lierre Keith, one of its founders, laid out the plan in a speech last year at an environmental conference at the University of Oregon.
"I would vastly prefer to wage this struggle non-violently," Keith said. "But my blogging will not bring forth the necessary numbers. So given a realistic assessment of what we actually have, the only viable strategy left that I can see is direct attacks against infrastructure. In the plainest terms, we need to stop them."
There was some controversy about inviting her to the conference. Other groups wanted her event cancelled because of her views on transgender people — Keith dismisses the notion that a sex change can undo someone's gender perspective.
Hildes said the FBI tried asking people about that Oregon speech. Since Yost's group was among those voicing opposition to DGR, she believes the FBI might be trying to sow division in the movement.
The Canadian government said it wasn't involved in any U.S. law-enforcement effort. A spokesman said it was aware of the megaload protests, but hadn't discussed them with any American agency.
Goodwin said he won't stop protesting. He's among the nearly 100,000 people who have signed a pledge to engage in civil disobedience, should the Obama administration approve the Keystone XL pipeline.
He called it a life mission to help thwart the development of the oilsands in Canada and the Bakken fields in the U.S. "If we don't stop that stuff we're never going to convert to alternative energies that don't pollute the atmosphere," he said.
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