Construction in Minnesota has bounced back from the Great Recession much faster than in Wisconsin, but not everyone agrees on why.

A new report from the North Star Policy Institute, a progressive think tank based in St. Paul, shows that Minnesota has seen stronger growth in both total construction employment and construction wages than Wisconsin since the financial crash a decade ago.

Using state and federal data, the authors say that both states lost about 32,000 construction jobs, about 25 percent of their total workforce, in the crash. By 2017, Minnesota had recovered all but 650 of the jobs lost since 2007, while Wisconsin still had about 8,800 to go, the report said.

Wage growth has favored Minnesota workers as well. Although both states saw wages fall in the recession, Minnesota’s average annual construction wage has risen by almost $6,800 since 2010, compared with a $4,700 increase in Wisconsin, according to the report.

The report’s authors believe a series of public investment projects probably helped Minnesota’s construction industry recover from the recession. Experts at the University of Minnesota and the Associated Builders and Contractors agree with that. But they disagree over how much of a role government actions, specifically policies toward unions in the two states, might have played.

“We don’t have any kind of metric model that we can plug variables into and do analysis on,” Jeff Van Wychen, a tax policy fellow at North Star Policy Institute and co-author of the report, said in an interview.

But the report still lists several factors the authors believe contributed to Minnesota’s recovery. Although they do not have figures for total infrastructure spending in each state, the authors note that Minnesota invested in major infrastructure projects like the Green Line light rail at the same time that Wisconsin was canceling a planned rail connection between Milwaukee and Madison and reducing other public spending.

Those investments certainly benefited Minnesota’s construction industry, said Peter Hilger, faculty director of the construction management program at the University of Minnesota. But Minnesota’s significant and often-contentious public investments wouldn’t be enough to shake off the recession on their own, Hilger said in an email.

“My conjecture is that the overall business economy that buys construction services was also perhaps a bit more robust,” he said, noting that Minnesota benefited from significant investment in medical facilities after the passage of the Affordable Care Act in 2010. “The public sector alone will not a recovery make. … Private investment must also be there, be it commercial or residential.”

The think-tank study authors also believe several anti-union policies adopted by Wisconsin hurt that state’s growth, said Lucas Franco, a co-author and researcher for the Laborers’ International Union of North America. Those moves include Wisconsin’s 2015 right-to-work law, prohibiting companies from requiring workers to be union members, and the 2011 law that limited collective bargaining for public employees.

Franco cites research by the Illinois Economic Policy Institute that found right-to-work laws reduced construction and extraction wages by 5.9 percent on average in Michigan, Indiana and Wisconsin.

“Our construction employment has been significantly stronger in Minnesota than Wisconsin, but what really stands out to me is the difference in wage growth,” he said, noting that Minnesota construction workers earn about $5,300 more than Wisconsin workers, compared with $3,650 in 2007. “[Minnesota and Wisconsin] started out with a wage gap, but that gap has grown significantly larger,” he said.

That interpretation is not universally shared outside the organized labor movement.

Minnesota’s construction industry has indeed had a strong recovery, said Adam Hanson, director of government and public affairs for the Associated Builders and Contractors of Minnesota and North Dakota. In fact, Associated Builders and Contractors has found Minnesota is tied for second-lowest construction industry unemployment in the country at 1.9 percent. However, the other state sharing second place is Iowa, which like Wisconsin is a right-to-work state and does not have prevailing wage laws, he said in an email.

Several major developments underway in Wisconsin, including a $10 billion plant in Mount Pleasant by Taiwan-based manufacturer Foxconn, will help close the gap that opened after the recession, Hanson said.

Minnesota’s total wage growth also isn’t the full story, Hanson said, noting the higher tax rates and cost of living in Minnesota, as well as the higher union density in Minnesota’s construction industry.

“How much of the ‘higher wages’ are actual take-home pay versus union political activity, union fair share fees, etc?” he said.

More research is needed to further isolate what factors have helped Minnesota’s construction economy since the recession, Franco said.

“We’re really trying to understand what has happened over the past 10 years,” he said. “… We’re excited to hear what other interpretations can come out of the data we reveal.”