FARMINGTON, N.M. (AP) – The Navajo Nation Council approved a measure that would allow disputes over a northwestern New Mexico coal mine being purchased by a tribal enterprise to be settled in state courts rather than tribal courts.

The council voted 17-5 in favor of the measure during a special session Friday in Window Rock, Ariz. Navajo President Ben Shelly signed the legislation following the vote.

A number of tribal delegates, attorneys and risk management experts met for about an hour in executive session before the vote, The Farmington Daily Times reported.

The legislation stems from a request by Zurich American Insurance Co. for the tribe to waive its sovereign immunity and settle any arbitration in New Mexico and Arizona courts. Zurich American and another company plan to issue $500 million in bonds and insurances to the Navajo Transitional Energy Co. to buy the mine.

Signs in opposition to the legislation and mine acquisition were posted and taped to flag poles outside council chambers.

Some delegates argued over whether the legislation needed to be approved by a supermajority of the council, as concerned community members and employees from Navajo Mine and the Four Corners Power Plant packed the council chamber’s public seating area.

Delegate Charles Damon drew criticism after motioning to rescind the supermajority requirement.

“What I am seeing now disturbs me. We are engaging in politicking in order to increase the chances of this legislation passing,” Delegate Lorenzo Curley said.

Critics of the legislation had argued that Navajo courts should not be eliminated from hearing any potential claims stemming from the mine. Delegate Russell Begaye said earlier this week that when companies conduct business in foreign countries, disputes are handled in that country’s courts.

“This mine is on our land, and these are guests to the nation,” he said during a debate Monday.