The 200-page American Federation of State, County and Municipal Employees Council 31 contract exemplifies how the demands of public employee unions have grown extreme in Illinois government and why Janus got fed up. Overtime costs, seniority rules, a hyperactive grievance process, pay raises and step increases that far outpace the consumer price index, health care plans heavily subsidized by taxpayers, costly pensions and worker protections that keep bad employees on the job have soured the image of public employee unions. They’ve gone too far.

Several years ago, a supervisor at the Illinois Department of Revenue made the mistake of working extra hours to reduce a backlog of tax returns. AFSCME filed a grievance. Why? She had violated a clause in the union’s contract by doing “bargaining unit” work. The union also filed complaints against volunteers at veterans homes who were giving their time, for free, to answer phones and welcome visitors. They were intruding on union workers’ turf.

The grievances were upheld through an arbitration process in Illinois that favors unions, not management. Embedded in public employee union psyche, that process codifies inefficiency in government. It’s coveted.

And taxpayers are on the hook. The union advocates for tax hikes and government growth — last year’s 32 percent income tax hike and now a proposed graduated income tax — to shore up its strength to the detriment of Illinoisans en masse. All those years of unbalanced state budgets and shortchanged pension funds? AFSCME, an ally of the Democratic majority, was an enabler.

On the political side, the union is an operative in political campaigns. Its leaders interview and endorse candidates up and down the ballot. They provide staff for petition-gathering and campaign strategy. They dump cash into dozens of races. They coordinate with other unions and political party officials to elect and defeat candidates.

From 2013 to 2017, 74 percent of the union’s political contributions went to Democratic committees or organizations, according to the Illinois Policy Institute, a right-leaning think tank. Six percent went toward Republican committees or organizations.

This is why Janus, a child support specialist at the Department of Healthcare and Human Services who lives in Springfield, grew increasingly frustrated, along with Gov. Bruce Rauner who filed the original case. Janus didn’t support the union’s posture on policy or politics, which are fundamentally intertwined. Yet AFSCME could snatch “fair share” dues from his state paycheck and he couldn’t stop it.

If the U.S. Supreme Court rules for Janus, it won’t mean public employee unions are dead in Illinois. What it will mean is that union leaders will have to work harder to persuade workers to keep paying. AFSCME will have to prove its worth.

If it does not, employees such as Janus can be let out of union membership and mandatory “fair share” fees. From the beginning, that’s all he wanted — to be his own advocate on the job, not a tool of a political organization whose activities he opposed. How many state workers will follow? Beware the stampede.