At the Convention Center on Monday, more than 6,000 cell biologists and life scientists from the American Society for Cell Biology and the European Molecular Biology Organization will focus on connections between cell biology and neurobiology.

Nearby, at the federal courthouse, there will be another gathering — of lawyers representing the Convention Center and the union carpenters who used to be the center's main labor force. The courthouse discussion will focus on a lawsuit over whether the union engaged in racketeering after it lost work at the center in May 2014.

Meanwhile, in Harrisburg, Pennsylvania Labor Relations Board hearing examiner Jack E. Marino has set Monday as the due date for briefs from the Northeast Regional Council of Carpenters (formerly the Metropolitan Regional Council) on whether the Convention Center committed an unfair labor practice when it ousted the union after its leaders didn't immediately sign a new customer-service agreement.

The leaders signed a few days later, but by then the traditional work had been divided among other unions.

Protests ensued. In May 2015, the Convention Center filed a federal civil racketeering lawsuit against the union, saying the protests, particularly a mass influx of carpenters into the center during the 2015 Philadelphia Auto Show, were part of a racketeering pattern to intimidate the center and its customers.

U.S. District Judge Nitza I. Quinones Alejandro ordered the parties to appear before a magistrate Monday, hoping they can be pushed to settle. Totally routine — happens in every big case.

About this time last year, there was a tentative detente, but it failed. Now, the sides can't even agree on discovery — the judge has to intervene. (Contributing to the delay was that the original judge in the case, U.S. District Judge Luis Felipe Restrepo, was promoted to the appellate court.)

If the carpenters lose, they'll owe triple damages.

At the PLRB, paperwork deadlines have been extended since March, when Marino conducted three long days of hearings into the issue. No matter what Marino decides, and probably not before March, it likely will be appealed to the full board, with that decision appealed to Commonwealth Court.

Still not completely resolved is whether the PLRB even has jurisdiction. That particular wrinkle included an episode in which Convention Center attorneys accused Marino of being unduly influenced by politicians when he changed his mind about jurisdiction, leaving Marino to conduct a hearing to determine whether he was fit to conduct hearings in the case.

If the Convention Center loses, it could owe the carpenters three-plus years of back wages.

There's a third piece of litigation, in which the carpenters and the Convention Center's labor broker are arguing over how much should be paid into the union's pension fund as a penalty for withdrawing from it. No matter what happens in these cases, legal fees are mounting.

"The Convention Center is always interested in settling disputes, but it is important that we do so in the manner that is consistent with our duty to our customers to provide a productive place to do business," said Gregory Fox, chairman of the Pennsylvania Convention Center Authority.

Fox said that business at the Convention Center has improved. "Bookings are one telltale sign of success,"  he said. Officials in Philadelphia's hospitality industry credit the new customer satisfaction agreement — the one the carpenters didn't sign in time, leading to their not working in the center — and new outside professional management that had experience dealing with unionized work forces in other convention centers and arenas.

Before those changes, which took place in late 2013 and 2014, customers had complained of high labor costs and hassles, and the center's management had been unable to address those concerns.

"It's very heartening to have the reverse of where we were five years ago," Fox said. "Customers are telling us what a successful show they had and how much they are looking forward to returning."

The head of the Philadelphia carpenters' union at the time, Edward J. Coryell, was ousted in February 2016 by the carpenters' top leadership in Washington, and replaced by John Ballantyne of Edison, N.J.

Ballantyne wouldn't talk about the Convention Center situation, instead sending this statement: "In response to the court order, the Northeast Regional Council of Carpenters will be participating this Monday in the settlement conference. Unfortunately, we cannot discuss any aspects of the settlement conference further at this time."