A new phase of the historic union vote by Amazon warehouse workers in Bessemer, Alabama begins today. The news kicks off with an appeals hearing where the Retail, Wholesale and Department Store Union (RWDSU) will contest the results of the election.

“Things are not over,” says Veena Dubal, a law professor at the University of California, Hastings. “We all need to be continuing to pay attention to this part.”

Earlier this year, after a months-long union busting campaign, workers voted 1,798 to 738 against forming a union. The decision was hailed as a crushing blow to the labor movement. But experts say the election was always going to be hotly contested. Even if RWDSU won, Amazon would almost certainly have fought the results, and the process would still have ended up in an appeal.

That wasn’t clear from the media coverage, which treated the election as the apex of the labor movement. “I think that it’s fair to say that very few people in labor actually thought that this was going to be a win,” Dubal says.

Witness testimony begins Monday, with RWDSU presenting evidence on each of its 23 objections. These range from Amazon installing a ballot collection box at the warehouse (allegedly giving the illusion that it controlled the vote) to threatening workers with pay cuts.

If RWDSU is successful, there would likely be another election, Bloomberg reports. But regardless of the outcome, Dubal says the campaign has already succeeded in spreading awareness. “The role that the Bessemer drive played was in part an attention getting campaign and a way to get America to look at the conditions in these warehouses,” she says. “It was still a very, very important drive, representing a cultural shift in people thinking about and talking about Amazon.”

The campaign also laid bare Amazon’s union busting tactics — typical for many companies — like bombarding workers with anti-union messages and requiring them to attend captive audience meetings. “Amazon has left no stone unturned in its efforts to gaslight its own employees,” RWDSU president Stuart Appelbaum said in a statement, which The Verge previously reported. “We won’t let Amazon’s lies, deception and illegal activities go unchallenged.”

Many of the tactics Amazon used are legal under current labor law. While the National Labor Relations Act is supposed to protect workers’ rights to organize, companies rarely face significant consequences for union busting.

That could change if the Protecting the Right to Organize Act (also known as the PRO Act) passes. The legislation would ban companies from holding captive audiences and it would establish fines for those that violate workers’ rights.

Dubal says that’s partly why the appeal hearing matters. “It’s imperative that we continue to pay attention to this,” she says. “It’s a learning moment. We are learning what is legal and illegal. We’re learning what companies do to suppress organizing. This needs to be public knowledge so that we understand why a law like the PRO Act is so important.”