The first courtroom arguments over a state law aimed at killing a coastal erosion lawsuit against more than 90 oil and gas companies will take place Monday, in the first of two hearings over the next several weeks that could determine the fate of the controversial case brought by the Southeast Louisiana Flood Protection Authority-East.

The constitutionality and applicability of that 2014 law, known as Act 544, are set to be argued in two different courtrooms, those of state Judge Janice Clark, of the 19th Judicial District Court in Baton Rouge, and of U.S. District Judge Nannette Jolivette Brown in New Orleans.

The state case starts this week; the federal case is set to be argued next month. And the complex relationship between the two court systems could mean a complex legal situation if those judges come to different conclusions.

“Assuming both courts go forward in parallel and there is a conflict in their rulings, this won’t be sorted out for much longer,” said Ed Sherman, a Tulane Law School professor who specializes in complex litigation.

Part of the federal case is the lawsuit itself, which alleges that oil and gas companies must bear part of the multibillion-dollar cost of restoring the state’s wetlands because of damage done by decades of drilling and dredging in the marshes.

The Legislature passed a law intended to retroactively kill that suit. The law had the support of Gov. Bobby Jindal, who has been a vocal opponent of the lawsuit and has tried to fill the flood protection authority with members who would vote to drop the case.

But while arguments about whether the law is constitutional and in fact applies to the flood protection authority’s lawsuit won’t be heard in federal court until November, Clark is preparing to hear similar arguments this week.

The state court case began late last year, when the Louisiana Oil and Gas Association sued Attorney General Buddy Caldwell in an attempt to invalidate the flood protection authority’s contract with its attorneys. Earlier this year, Clark threw out the association’s claims that the authority could not hire outside counsel and that the Attorney General’s Office should not have allowed it to enter into the contract with its lawyers.

But some issues in that suit were never resolved, such as whether LOGA should have to pay court costs. That lack of a final ruling has prevented LOGA from appealing Clark’s ruling, as it wanted. But those outstanding issues also have opened the door to arguments by the flood protection authority’s lawyers, who intervened in the case, that the state court also should weigh in on Act 544.

Both the Jindal administration and LOGA have referred to that effort as “forum shopping” and an attempt to make sure the case is before a sympathetic judge.

“This issue doesn’t belong in this proceeding,” Jindal spokeswoman Shannon Bates said. “This is the trial lawyers’ latest attempt to keep a frivolous lawsuit alive, and it’s wasting taxpayer dollars.”

But Gladstone Jones, who has led the team of lawyers working for the flood protection authority, dismissed that argument.

“You can’t forum shop when you didn’t file the damn lawsuit. They filed the suit against us,” Jones said.

A win for the flood protection authority in Clark’s court wouldn’t necessarily mean the authority is in the clear on proceeding with its suit against the energy companies. State courts can’t force federal courts to abide by their decisions. That doesn’t, however, mean the state court’s decision wouldn’t have an effect on the federal case.

“The plaintiffs may figure the short-term tactical advantage is if they get a state court to rule that this law wasn’t intended to apply” to the authority’s suit, Sherman said. “A federal court may not be bound by it, but it might be persuasive to the federal judge.”

In addition, the state court case eventually could reach the state Supreme Court, and federal courts typically defer to decisions by that body, he said.

Given the stakes, it’s likely that the upcoming hearings are just the first steps in what could be a long process.

“Because so much money is involved, it’s going to be taken to the very farthest point that anyone has a right to appeal,” Sherman said.

Success in state court would also hand the flood protection authority a public relations victory. That, in turn, could be valuable in an aspect of the case that has gone on behind closed doors: discussions with the oil and gas companies about settling the case.

Lawyers and flood authority members have hinted that negotiations have been going on for months with at least some of the scores of defendants, though details on those talks have been kept under wraps. Any setbacks for efforts to kill the suit, such as last week’s renomination of pro-lawsuit Commissioner Paul Kemp, could provide more leverage for the authority in those negotiations and nudge any companies that are on the fence toward agreeing to a settlement.

In both courts, the flood protection authority is challenging the 2014 law on constitutional grounds that include procedural issues with the way it made its way through the Legislature. Similar arguments played a role in the state Supreme Court’s 2013 ruling that a law providing financing for the state’s voucher program was unconstitutional.

But the flood authority’s lawyers also argue that even if it stands, Act 544 was drafted poorly and does not actually affect their case. They say that the specific language used in the law to refer to the levee authority — a “local governmental entity” — is defined under state law as referring to a parish government and that the type of claims that would be barred by the law are different from those that are being brought in the lawsuit.

Courts typically look to “legislative intent” only if there are multiple ways to interpret the same law and not in cases where a law simply does not do what it was supposed to do, Sherman said.

“The legislative intent couldn’t be more clear, and the law they wrote couldn’t be more clear,” Jones said. “They just are in opposition.”

Follow Jeff Adelson on Twitter, @jadelson.