WASHINGTON (AP) -- Powerful public-sector unions are facing another high-profile legal challenge that they say could wipe away millions from their bank accounts and make it tougher for them to survive.
A group of California schoolteachers, backed by a conservative group, has asked the Supreme Court to rule that unions representing government workers can't collect fees from those who choose not to join.
Half the states currently require state workers represented by a union to pay "fair share" fees that cover bargaining costs, even if they are not members. The justices could decide as early as next week whether to take up the case.
Union opponents say it violates First Amendment rights to require nonmembers to pay fees that may go to causes they don't support. They could find a sympathetic ear at the high court, where the justices last year indicated they may be willing to reconsider a 38-year-old precedent that allows unions to collect the fees.
The high court's 1977 ruling in Abood v. Detroit Board of Education said public workers who choose not to join a union can be required to pay for bargaining costs, as long as the fees don't go for political purposes. The arrangement was supposed to help promote labor peace and prevent nonmembers from "free riding," since the union has a legal duty to represent all workers.
But the Center for Individual Rights, which is representing the plaintiffs, says even basic union goals such as increasing school budgets and seeking pay raises for teachers are tinged with partisan beliefs that can clash with the views of school workers.
"In our view, when a public employee union negotiates with a local government over the use of tax money, it's an inherently political negotiation," said Terry Pell, the group's president.
The lead plaintiff in the case is Rebecca Friedrichs, a veteran public school teacher in Orange County, California, who says she resigned from the teachers' union because she disagrees with its political views and its collective bargaining positions.
A federal district court ruled against the challengers, saying the outcome was clear under Abood. The 9th U.S. Circuit Court of Appeals affirmed.
The Supreme Court raised serious doubts about the viability of Abood last year, when it ruled 5-4 that thousands of home health care workers in Illinois could not be required to pay union fees that cover collective bargaining. The court stopped short of overturning the case, but Justice Samuel Alito's majority opinion called Abood "questionable on several grounds."
Alito had also criticized the Abood decision in a 2012 opinion in which the court ruled that union members had to opt in for special fees instead of opting out.
"It's a clear signal that Alito believes Abood ought to be overruled," said Benjamin Sachs, a professor at Harvard Law School specializing in labor law. "There are some number of justices on the court that probably share that view."
Yet it may be that Alito can't find four other justices to go along with him. The Supreme Court has been reluctant to overturn longstanding court precedent.
If the high court takes the latest case and rules against the union, labor officials say it could sap finances at all unions representing teachers, firefighters and other government workers. It could also lead to the exodus of thousands of union members who will wonder why they should pay union dues at all if nonmembers get the same representation for free. The union would still have a duty to represent workers who pay nothing.
"I think it is an attempt to reduce our numbers, reduce our clout and reduce our revenue streams," said Frank Wells, spokesman for the California Teachers Association.
Unions have spent hundreds of millions to bolster Democratic Party candidates and other partisan issues in state and federal elections. The California Teachers Association spent more than $211 million in political expenditures from 2000 to 2009, including $26 million opposing school vouchers.
Conservative groups argue that eliminating mandatory union fees may actually make unions stronger by forcing them to prove their value.
The case comes as officials in Wisconsin and other states dealing with budget deficits have worked to reduce bargaining rights for public employees. Public-sector workers have a union membership rate of 35.7 percent, more than five times higher than that of private-sector workers at 6.6 percent, according to the U.S. Bureau of Labor Statistics.
Overall union membership in the 25 right-to-work states that prevent unions from collecting nonmember fees was only 6.7 percent last year, compared to 13.8 percent in states allowing the fees.