The Wall Street Journal:

The Supreme Court has barred public-employee contracts requiring workers to pay union dues, dealing a severe blow to perhaps the strongest remaining redoubt of the American labor movement.

The 5-4 vote, along conservative-liberal lines, on Wednesday overruled a 1977 precedent that had fueled the growth of public-sector unionization even as representation has withered in private industry. More than one-third of public employees are unionized, compared with just 6.5% of those in the private sector, according to a January report from the Bureau of Labor Statistics.

The impact of the ruling is likely to stretch far beyond the workplace, sapping resources from unions such as the American Federation of State, County and Municipal Employees and the National Education Association that have provided funds, resources and activists largely in support of Democratic candidates. In the 2016 election cycle, public-sector unions spent $64.6 million on political activities, and 90% of that went to Democrats, according to the Center for Responsive Politics. The largest spenders were the nation’s two biggest teachers’ unions and AFSCME.

Still, total spending by all labor unions, $213.3 million in the 2016 cycle, was small relative to the $3.43 billion spent by businesses. That business spending was split evenly between Democrats and Republicans.

Unions, which long have anticipated this day, have been preparing strategies to retain membership, but significant drops in support are likely.

Justice Samuel Alito, whose opinions have shaped the court’s turn against public-sector unions, wrote for the majority.

“Compelling individuals to mouth support for views they find objectionable,” even if they are part of collective bargaining that benefits that employee, affronts a “cardinal constitutional command,” he wrote. Justice Alito quoted Justice Robert Jackson’s 1943 opinion forbidding mandatory recitation of the flag salute in public school: the government may not “force citizens to confess by word or act” any opinion.

“In most contexts, any such effort would be universally condemned,” Justice Alito wrote, joined by Chief Justice John Roberts and Justices Anthony Kennedy, Clarence Thomas and Neil Gorsuch. Nothing about this particular context—states that had authorized public agencies to negotiate labor contracts similar to those in the private sector, and state and local bodies that approved such contracts—called for any different response, he said.

Plaintiff Mark Janus said he was “thrilled that the Supreme Court has restored not only my First Amendment rights, but the rights of millions of other government workers across the country.” Mr. Janus, a child-support specialist for the state government in Springfield, Ill., objected to a $45 monthly payroll deduction for Afscme Council 31, which negotiated the contract providing him wages and benefits.

“The right to say ‘no’ to a union is just as important as the right to say ‘yes,’” said Mr. Janus, who was recruited by the National Right to Work Legal Defense Foundation to serve as plaintiff after Illinois Gov. Bruce Rauner, a Republican who initiated the case, was dismissed from the suit on procedural grounds.

For the court’s liberals, the decision Wednesday—the final day of this term—capped a term replete with disappointment.

“There’s no sugarcoating today’s opinion,” Justice Elena Kagan said from the bench. The majority, acting as “black-robed rulers overriding citizens’ choices,” had stopped “the American people, acting through their state and local officials, from making important choices about workplace governance,” she said.

Joined by Justices Ruth Bader Ginsburg, Stephen Breyer and Sonia Sotomayor, Justice Kagan accused the majority of “weaponizing the First Amendment, in a way that unleashes judges, now and in the future, to intervene in economic and regulatory policy.”

Some 20 states, principally in liberal-leaning regions such as the Northeast and the Pacific Coast, permit government agencies to reach union-security agreements with labor organizations, requiring employees within a bargaining unit either to join the union or pay it a fee for core services, such as negotiating and enforcing contracts.

Unions, which call such charges “fair-share fees,” say they are necessary to prevent free riders—employees who are happy to receive the raises, benefits and job security a union contract offers but prefer to let their co-workers foot the bill.

Although the government must respect many of its employees’ constitutional rights, a line of Supreme Court precedent gives public agencies more leeway when they act as employers, reasoning that managers need discretion in how they run their shops.

The 1977 precedent that the court has now overturned, Abood v. Detroit Board of Education, reasoned that a public agency might find it beneficial to accept a union-security clause for the same reasons a private company might—ensuring labor peace, avoiding strikes and the like.

Abood held that objectors cannot be charged for union activities beyond collective bargaining, such as political campaigning.

But after the court tilted further to the right in 2006, with the appointment of Justice Alito, antiunion groups developed a challenge on the premise that anything a union does in relation to a government agency, including bargaining, is inherently political, because elected officials ultimately are responsible for its decisions.

Under that theory, it would violate the First Amendment for government to condition a job on subsidizing political speech a worker may oppose—and therefore public-employment contracts including union-security clauses would be unconstitutional. The court majority has now accepted that argument.

A pair of prior Alito opinions, adopted by 5-4 votes, had signaled to conservatives that justices would be receptive to that theory, and the court appeared poised to overrule the Abood precedent after arguments in January 2016. But with the death of Justice Antonin Scalia a month later, the court deadlocked 4-4 and left the 1977 rule in place.

After President Donald Trump appointed Justice Neil Gorsuch to the vacancy, however, it was clear that the reckoning for public-sector unions had only temporarily been postponed. Illinois, where Republican Gov. Rauner has been locked in conflict with public-employee unions since taking office in 2015, supplied the vehicle.

The theory behind Wednesday’s decision poses no immediate threat to union-security clauses in private-sector contracts. Unlike government agencies, private businesses generally aren’t required to respect free-speech rights and can establish various conditions of employment, including requiring fair-share fees, if permitted by state law.

This all started here in Wisconsin with Act 10 and Recallarama earlier this decade. Voters in this state twice decided that government employee unions should not have more power than taxpayers.