Gov. Tim Walz infuriated many Republicans and some DFLers last month when he decided to continue a legal challenge against a controversial oil pipeline planned in northern Minnesota.

Now, supporters of Enbridge’s Line 3 project have loudly underscored their dissatisfaction.

The Republican-led state Senate plans to vote Thursday on a bill that aims to block the Walz administration from using taxpayer money to file a lawsuit related to the $2.6 billion pipeline.

Senate File 1757, sponsored by Sen. Paul Utke, R-Park Rapids, would prohibit Minnesota’s Department of Commerce from spending money from its budget to appeal a decision by the Public Utilities Commission to grant the pipeline a Certificate of Need. It passed on a 34-30 vote.

While the measure is unlikely to gain traction in the House, which is controlled by a DFL majority, Senate Majority Leader Paul Gazelka, R-Nisswa, said the bill’s passage serves as a message to Walz. Sen. Justin Eichorn, a Republican from Grand Rapids, said the measure was a “serious proposal” and not “just a ‘poke the governor in the eye’ proposal.”

“When we’re spending taxpayer dollars to sue ourselves it’s kind of obvious why there’s a lot of people on both sides of the aisle, and especially in the middle, that have a problem with that,” Eichorn said. “And so that’s why I think it’s important to have the discussion on that bill.”

Before the vote Thursday, many DFLers accused Republicans of trying to meddle with another branch of government and said the GOP wouldn’t try to intervene if Commerce was suing to help a project they supported. “This isn’t about the pipeline, this is about checks and balances,” Sen. Nick Frentz, DFL-North Mankato, said in a speech from the Senate floor.

Commerce commissioner Steve Kelley said the bill “sets a dangerous precedent in terms of separation of powers.”

“The legislative attempt to change the legal process for this Line 3 case – and only this particular case – by crippling a state agency’s ability to see a case through to the end of the normal process of appeal is an overreach by the Legislature,” Kelley said.

Former Gov. Mark Dayton was the first to appeal the PUC’s decision. His administration claimed Enbridge had not cleared a legal bar to get PUC approval by properly proving demand for the oil. But his lawsuit was thrown out on a technicality shortly into Walz’s tenure.

Walz faced intense lobbying while mulling whether to restart the legal challenge. He eventually decided Enbridge had not done enough to win public trust in the project.

“My take is, if you can’t get people’s buy-in, to believe that there’s validity behind the discussion — the social permit — it makes it very difficult to get these done without great disruption,” Walz said in February.

A petition for reconsideration filed with the PUC by the Commerce department, a precursor to a lawsuit, was shot down unanimously this week by the commissioners, all of whom were appointed by Dayton.

Enbridge hopes to build Line 3 to take the place of an existing one. The current 34-inch Line 3 pipeline was built in the 1960s and is corroding and operating at half capacity. The new 36-inch pipeline would run through a different 337-mile route in northern Minnesota, crossing through the headwaters region of the Mississippi River and carrying about 760,000 barrels of oil each day to a terminal in Superior, Wisconsin. It starts in Edmonton.

While supporters of Line 3 say a new pipeline would be safer than continuing to use an older pipeline or transporting oil by rail or other means, its opponents contend Minnesota should not approve more fossil fuel infrastructure, and warn of potential oil spills.

“With their approval of Line 3, the PUC is ignoring serious threats to Minnesota’s clean water and the wishes of the communities that would be directly affected by this dirty tar sands pipeline,” Margaret Levin, director of the Sierra Club North Star Chapter, said in a written statement this week after the PUC voted down Walz’s petition for reconsideration.

Katie Sieben, a PUC commissioner and a former DFL state senator, admonished the Commerce Department for continuing its lawsuit. “For the department to argue that the commission should ignore the current condition of the very infrastructure that is to be replaced is nonsensical,” Sieben said at the PUC vote. “Further, the alternative was to have oil cross Minnesota in a corroded pipe, and in rail cars and on highways.”

Enbridge had hoped to start construction this year and begin shipping oil by the end of 2019, but it recently announced a roughly yearlong delay while it works to secure state permits.