The U.S. Supreme Court has held that labor unions may collect fees from nonunion workers to cover the costs of collective bargaining performed on their behalf. But the court has further held that's all they can take -- the unions are forbidden from collecting and using additional fees from nonunion workers to finance union political activities, unless those workers grant their permission.

Otherwise, workers who choose not to join a union but who are nonetheless assessed "bargaining" fees could end up being required to pay for partisan politicking they may oppose, violating the free speech and association clauses of the First Amendment.

But how much -- and what kind of -- "permission" is necessary?

The high court Wednesday heard arguments on two consolidated cases out of Washington state that raise just that question.

At issue are the fees collected by Washington state's teachers union, the WEA. If you want to be a teacher in Washington, you have to pay a fee to the union, even if you aren't a member.

That's because the state Legislature assigned exclusive authority to the union to bargain for pay and other employment matters for all teachers. Nonunion teachers see deductions equal to the union dues withheld from their paychecks.

But a 1992 state campaign-finance law mandates that the 80,000-member union obtain the consent of some 3,000 nonmember teachers before using any portion of their dues for politicking.

The narrow issue before the justices is whether employees must opt in -- affirmatively consent -- to having some of their money used in election campaigns.

Union officials say they obtain that consent by offering nonmembers the option of objecting to the political use of their fees. Twice a year, the WEA mails a packet of information to nonmembers telling them they have a right to object to the use of their fees for politics.

If they object, the money is refunded. But if they do nothing, forget or otherwise fail to properly return a form within the 30-day deadline, the union interprets that as permission to use the money for political purposes.

Plaintiffs -- a group of current and former teachers -- complain that's not enough. They say the state law requires prior authorization -- an "opt-in" system. If no such prior consent is given, the money is off limits for political purposes and must be refunded, they argue.

Weirdly, despite the specific language of the law, the Washington state Supreme Court sided with the union, declaring by a 6-3 vote that the state's tougher affirmative consent law violated the WEA's free speech "right" to use union funds for political advocacy without facing government-imposed restraints.

"The union's [opt-out] procedures amount to a constitutionally permissible alternative that adequately protects both the union and dissenters," the state court declared.

But that logic "turns the First Amendment on its head," Justice Richard Sanders wrote in dissent.

Precisely. As author Geoff Leff pointed out in a recent commentary, "The First Amendment protects the rights of individuals and organizations to freely associate and express themselves." But to truly do that, it must also protect their rights "not to associate and not to be compelled to support expressions they oppose."

The amounts involved are not paltry. In previous cases, courts have found that unions often spend a majority of their funds on things that aren't related to collective bargaining. The U.S. Supreme Court's 1988 Beck case found only 21 percent of the union's spending was legally chargeable to non-members, Mr. Leff notes.

Debra Carnes, a spokeswoman for the WEA, agrees it's all about the money, arguing the legal battle is aimed at undercutting the power of unions. "This is much bigger than WEA and opt-in or opt-out," she says. "The goal is to dry up the money so unions have no collective voice."

But the only money that might be "dried up" is nonmembers' money to which the unions had no right in the first place. And if Ms. Carnes believes nonmembers will withdraw most of their 4 percent of the union's political funds if given the chance, isn't that a tacit admission that the current "opt-out" arrangement has the effect of denying them that free choice?

Here's hoping the court gives Washington's nonunion teachers their refunds.