Illinois' workers' compensation wars usually pit blue collar workers and their unions against manufacturers and builders over how much someone ought to get paid when they're hurt on the job. Legislators have tried to referee that fight for decades, with mixed results.

However, workers' comp costs also accrue in the public sector. Now a new report by the Illinois Policy Institute puts a price tag on how much state and local governments—taxpayers—collectively have to pay annually in workers' comp premiums and related costs here.

The figure: roughly $1 billion a year.

According to an institute study being released today, workers' comp costs at the state level run an estimated $255 million a year, and in local government—cities and towns, townships, school districts, park districts and more—about $727 million more.

That comes up to a combined $982 million, about 4 percent of payroll. The total number is almost certainly higher because the institute was able to get only partial information from the city of Chicago. (Chicago officials tell me the cost to the city alone runs about $100 million a year.)

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If those costs were lowered to the average of other Midwest states, state and local governments collectively would save about $300 million a year, the institute contends.

Now, the institute definitely is on the conservative side. The libertarian group has been allied with Gov. Bruce Rauner in his efforts in Springfield to trim spending on workers' comp and other items.

But the group's basic math, if not necessarily its solutions, usually have a foundation. Brad Cole, executive director of the Illinois Municipal League, says the top-line numbers here seem about right.

"I always figured 5 percent of payroll (for workers' comp)," says Cole, the former mayor of Carbondale. "I haven't seen their report yet, but I think their numbers are reasonably accurate. Some of the items they talk about have a considerable cost."

"Some of the items" is a reference to where the institute would cut workers' comp, and its list is likely to be as controversial as its top-line number is big.

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Among other things, the institute would repeal workers' comp enhancements signed into law by former Gov. Rod Blagojevich, tie fees and awards more closely to Medicare and American Medical Association standards, cap wage-reimbursement rates to workers at 100 percent of the state's average weekly wage and require those recovering from injuries to assume light duties when they can.

Another idea: Allow physicians to sell pain-killing opioids for only a few days after they first see an injured patient. After that period, the patient would have to get their prescription filled at a pharmacy, reducing—in the institute's view—financial incentives for doctors to overprescribe.

I've asked a labor group for its take on all of this, and will add it in when I get it. The traditional argument is that hurt workers deserve every penny of what they get and that previous legislation already has cut costs.

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But the institute's Mike Lucci, echoing an argument Rauner has made in fights with Democratic leaders, maintains something needs to be done.

"Illinois should set the goal of aligning its workers' compensation costs with those of other states in the region," he says. "Businesses are leaving Illinois in the dust when they invest in neighboring states that have lower costs and more pro-growth reforms."