PRINCE RUPERT, B.C. - There have been times over the past few days at the review hearings into the proposed Northern Gateway pipeline when the testy exchanges between Enbridge experts and First Nations lawyers have bordered on verbal warfare.

And as the proposal progresses, it seems increasingly likely that the debate about the oil pipeline — an oil pipeline, any oil pipeline — will end in a showdown between the federal government and First Nations over aboriginal rights.

"I think on the First Nations side, there's no question they're marshalling resources to go to court," said Gordon Christie, director of indigenous legal studies in the University of British Columbia's faculty of law.

As lawyers for the Haisla Nation questioned company experts in Prince Rupert on Thursday, 1,500 kilometres south in Vancouver, the Tahltan Nation and the B.C. Metis Federation announced that they have added their names to a petition banning oil pipelines and tankers from traditional territories.

The proposed pipeline route doesn't actually enter Tahltan territory around Stewart, B.C., and the B.C. Metis Federation does not have traditional lands.

But Chief Martin Louie of the Nadleh Whu'ten First Nation said it shows pipeline opposition is gaining momentum.

"Whether in the north or the south, we are all threatened and we are all connected," the Yinka Dene said in a letter inviting the Metis to join the campaign against Northern Gateway and the Trans Mountain pipeline project.

The petition launched by the Yinka-Dene now has more than 130 bands on board. It bans pipelines and tankers in the Fraser River watershed, as well as oil tankers in the ocean migration routes of Fraser River salmon.

Petition organizers say signatory First Nations form an unbroken chain that spans the entire length of the province.

Unlike other provinces, First Nations in B.C. did not sign treaties with the colonial government, and decades of modern-day treaty negotiations have largely failed.

"We know they have aboriginal rights. We just don't know what they are," Christie said. "There hasn't been a treaty or any court cases to set out what they are."

Courts have ruled that the Crown has a duty to consult aboriginal groups, but whether it has a duty to gain their consent is unclear. Certainly, several of the bands opposing the Northern Gateway project see it that way.

"Our rights are protected under Section 35 of the Constitution. We will not allow government to impose the Enbridge pipeline and tankers on us," Louie said in a statement Thursday.

He echoed a sentiment expressed by several First Nations along the pipeline route, so even if the panel decides the project can go ahead and the federal Natural Resources minister approves, the project proposal will very likely end up — eventually — in front of the Supreme Court of Canada.

Whether the current panel process suffices as the Crown's legal obligation to consult, that will be up to the court to decide.

In Alberta, industry has successfully bypassed the tense relationship between First Nations and the federal government, and opted to seek approval directly from aboriginal bands.

In the case of Northern Gateway, the company has offered equity stakes, procurement opportunities and skills development. They've included cultural use studies and several times a day, under hours of questioning, Enbridge experts renew an offer for aboriginal involvement in the planning process.

"We want Aboriginal economic participation in this project," said spokesman Todd Nogier.

Enbridge has been consulting communities for over 10 years, he said, and have developed a package of economic and social commitments.

"In fact, it is safe to say our consultations have surpassed those of any other energy infrastructure proposals in Canadian history."

The company has offered an estimated $100 million over 30 years for a community fund, and funds for a regional Fisheries Liaison Committee.

"There is no legal obligation on Enbridge to consult. That's entirely on the Crown," Christie said. "They (Ottawa) seem to be trying to pass that off to Enbridge and they can't do that."

If the case does go to court, the outcome is unclear, Christie said, but the lengthy process might just mean they win even if they lose.

"Enbridge might start to wonder whether it's a good idea," he said.

Janet Holder, vice-president of western access for Enbridge, was asked this week in Prince Rupert whether the company had decided on any limits in the timeline or costs.

Holder said they have not made any decisions on that issue and are focused on allowing the review process to unfold.

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