New Yorkers have little reason to be grateful to Roger Toussaint, the leader of the Transit Workers Union that crippled the city last December in an illegal strike, but he deserves credit for one good deed, albeit an unwitting one – he has made New York a right-to-work city, at least temporarily. A state judge in Brooklyn, Theodore T. Jones, has fined the TWU $2.5 million for violating the state’s Taylor Law against public-sector strikes. Not only that, but the judge has also suspended for 90 days automatic deduction of union dues from members’ paychecks. Even after the three months are up, the union will still have to convince the judge to allow the deductions again.

This, and not the headline-grabbing fine, could prove the real punch to the union, which now needs to find some way to make sure all its members voluntarily send in their dues without the coercion of an automatic deduction. Lawyers for the TWU certainly recognized the threat, arguing that blocking the deductions would wreak havoc on the union’s cash flow. The union’s leader apparently values the deductions more than his own freedom; Mr. Toussaint has said he will not appeal the judge’s April 11 decision in which he was sentenced to 10 days in jail, but the union has announced that it will appeal the judge’s latest ruling.

Already yesterday the hyperbole was flooding from the unions. “We find this decision unfair,” Mr. Toussaint was quoted as saying in press reports before going on to blame the Metropolitan Transportation Authority for his union’s woes: “The MTA engaged in the provocation that led to this strike.” The president of the United Federation of Teachers, Randi Weingarten, picked up the refrain: “This is further proof that the Taylor Law is completely stacked against municipal workers and is in drastic need of reform. The Taylor Law does not allow the judge to consider the fact that the MTA had a huge budget surplus and acted in such a provocative manner.”

Well, what the ruling really proves is that crime doesn’t pay. The law of the land, and in particular New York’s Taylor Law, forbids strikes such as the walkout perpetrated by the subway and bus drivers. The MTA’s surplus or any alleged provocation doesn’t change that fact. Abiding by the Taylor Law, with its limits on public unions’ ability to extract more money from taxpayers in contract negotiations, is the price people pay when they go to work for the government, and now, if the appeals courts stay strong, the union will pay the price for breaking the law.

Ms. Weingarten argues that “the sole purpose of a ruling like this is to emasculate a labor union. “The Taylor Law is actually a “private-public equalization law.” Private-sector workers, even unionized ones, face a lot of risks, as the pilots at United Airlines discovered when their pensions were dramatically reduced during that company’s bankruptcy. New York’s public employees, in contrast, are almost immune to any risk of being fired; even their pensions are constitutionally protected. They need not worry, as the United Auto Workers, say, increasingly must, that extracting too generous compensation will push their employer into default on all compensation. This is why the law requires public unions give up some of their leverage in the contract negotiations that extract their generous, taxpayer-backed benefits.

The latest ruling in this case will remind the union that nothing in life is free, not even a government job. It is also, incidentally, a boon for members of the TWU who have realized, after having their individual paychecks docked for participating in the strike, that there is nothing to be gained from breaking the law. As long as the judge’s ruling is in effect, the law-abiding members of the union will not be forced to subsidize their lawbreaking leadership. The city will finally find out, based on how many members actually pay dues, for whom the union leadership speaks. The rank and file will now have an opportunity to exert real leverage on their leaders.