The U.S. Supreme Court has agreed to hear a case which has sparked concerns that public-sector unions may soon face a significant decline in membership.

Lead plaintiff Mark Janus filed the lawsuit with two other Illinois state workers. Their challenge seeks to end mandatory union dues for all public-sector workers. Labor unions and their supporters denounced the lawsuit as an underhanded attack to defund unions by taking away dues-paying members.

Those concerns assume a lot about how public-sector union members will respond. Making union dues and fees optional for all public-sector workers is unprecedented so the actual outcome is unknown. But the impact does have the potential to be significant with so many union members at play.

“This has some real big picture implications for various reasons,” James Plunkett, senior counsel for the employer-based law firm Ogletree Deakins, told InsideSources. “If the court rules in favor of Mr. Janus, how does that impact public-sector unions? I think that this is a vitally important case for the unions.”

Labor unions and their supporters argue that optional dues encourage workers to free-ride. Workers might decide not to fund their union knowing that they will get the benefits anyways. Critics counter that it’s really about giving workers a choice instead of forcing them to fund an organization they might not support.

“I don’t think it’s going to be their destruction,” Renne Sloan Holtzman Sakai partner Tim Yeung told InsideSources. “But it’s going to lessen the money, to some extent, that they have to use … I think practically there is going to be some effect. But I don’t think it’s going to be the destruction of unions.”

Experts do have some examples to draw on that show how optional dues might impact public-sector workers. Wisconsin saw a significant decline in membership rates when they made dues optional. Federal workers, in contrast, have had the option for years but still maintain fairly steady membership rates.

Labor unions have plenty of reason to be concerned. The Bureau of Labor Statistics (BLS) found that the public-sector has the highest rate of unionized workers at 34.4 percent. In the private-sector, only 6.4 percent of workers are unionized.

“I’m sure, given the choice, there is going to be some number of government employees who are currently forced to pay dues or agency fees, who will decide that its no longer in their best interest to do so,” Nelson Cary, partner for the law firm Vorys, Sater, Seymour, and Pease, told InsideSources. “The most recent example that I’m aware of, and maybe the best empirical basis on which to draw from, would be the experience in Wisconsin.”

Wisconsin Republican Gov. Scott Walker earned his reputation on how he reformed labor policy in his state. Act 10 allowed state employees to choose whether they wanted to pay union dues when it was passed in 2011. The union membership rate in the state dropped from 14.1  percent to just 9.0 percent by 2016.

“It’s a big source of revenue for the labor unions,” Plunkett, who previously served as the director of labor law at the U.S. Chamber of Commerce, said. “If the public-sector employees aren’t forced or compelled to pay union fees as a condition of employment, as we’ve seen in Wisconsin, many of them will choose not to do so.”

Labor unions were already facing a decades-long decline in membership rates before the lawsuit came around. Former President Barack Obama argued on numerous occasions during his time in office that unions were critical to protecting workers. His administration implemented regulations to help bolster membership.

“But ultimately, what’s going to improve the union membership rate is providing a better product,” Plunkett said. “Even with the rules changed, they’re still struggling. To me, that seems like the product is lousy.”

Employees who do not wish to belong to their workplace union can be required to pay a fee in many states. That fee can only cover collective bargaining costs and not political activities. The lawsuit argues public-sector collective bargaining and political lobbying are indistinguishable.

Wisconsin has seen a significant decline in union members since their labor reforms. But the state merely provides an example of what might happen if all public-sector workers gained the right to choose. Yeung notes that the impact might not be the same across all unions with some deciding to stay together even when they have a choice.

“At least here in California, you have certain types of unions, especially those representing firefighters, police officers, nurses, and to some extent teachers,” Yeung, who practices labor and employment law, said. “They are very well organized and I think the impact on those unions won’t be great.”

Yeung adds those unions tend to have a notable level of camaraderie. Others public-sector unions, however, might be greatly impacted as members find various reasons to leave. Yeung sees the biggest impact happening in those unions that represent public-sector workers who do more blue-collar type jobs.

“Where I think we’re going to see the big hit is a lot of these blue collar workers,” Yeung said. “Here in California, the state and some of the big agencies, upwards of 50 percent of a particular bargaining unit may be what we call agency fee payers. So the worst case scenario is losing 50 percent of their funding which would be devastating.”

Unions believe many workers may leave knowing that the unions will legally have to represent them regardless of whether they pay dues. Others suggest that many workers may choose to leave simply because they don’t like the service the union is providing. Plunkett notes that unions need to be thinking about the service they provide.

“If I were the unions, that’s what I’d really be thinking about doing,” Plunkett said. “I wouldn’t just say well we’re doing okay in the federal sector so maybe we’ll just wait this out. I think they’re really going to want to start reforming their message and what they can offer workers.”

The National Right to Work Legal Defense Foundation (NRTW) has been assisting in the lawsuit alongside the Liberty Justice Center (LJC). The lawsuit aims at reversing a 1977 ruling by the Supreme Court which affirmed the right of labor groups to collect fees from workers who did not want to belong to their workplace union.

“There are all sorts of ways the cookie can crumble here without getting a clear black and white decision,” Plunkett said. “That’s what’s in the back of my mind, to be honest. Is there someway for the court to decide this case in a way that punts it again?”

California teacher Rebecca Friedrichs challenged her union in a similar case that went to the Supreme Court last year. The court became split after the death of Justice Antonin Scalia. A tied decision defaults to the lower courts, which ruled against the lawsuit. Justice Neil Gorsuch has since filled the vacant seat.

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