It's always been annoying to hear people bitch about being "forced" to pay their union dues, especially when you don't hear them pushing to negotiate their own damned salaries. But I guess we all knew this was coming:

WASHINGTON -- The Supreme Court signaled Tuesday that it may be prepared to strike down laws forcing public employees to pay union dues, posing a major threat to organized labor.

The justices agreed to hear a California case next fall challenging the requirement that teachers contribute to unions, even if they don't join them or agree with their positions on issues.

Two lower courts upheld that arrangement, but the high court in recent years has been hostile to the so-called "agency shop" rules. In two prior cases, Justice Samuel Alito has written majority opinions scaling back on the requirement.

Under the court's 1977 precedent, unions largely have been allowed to collect dues from all private or public employees they represent. Those who object don't have to contribute to political or lobbying activities, but they must chip in for the unions' efforts in fighting for better wages, benefits and working conditions.

But in the most recent case last year, the court ruled 5-4 along ideological lines that home-care workers in Illinois do not have to pay dues to public employee unions. The workers said the unions lobbied the government, often on issues the workers oppose -- thereby abridging their First Amendment rights.

In his ruling, Alito said that except in rare circumstances, "no person in this country may be compelled to subsidize speech by a third party that he or she does not wish to support."