There is much in the way of scholarly research done on the subject of right-to-work laws and their impacts on everything from union membership to wages and economic impacts on workers and businesses. For this review, we focus on research with findings related to employment outcomes, because that is primarily what this study measures. We also confine the review to papers published since the Mackinac Center’s 2013 right-to-work study was published, which contained its own literature review.[12] We further narrowed our review to research that cited the 1998 Holmes study, because that methodology was the largest influence on the modeling used in this study.[*]
There is one exception which involved methodological considerations that fed the construction of our own model and measuring techniques, and which we describe directly below. Economists Charlene Kalenkoski and Donald Lacombe’s 2006 paper, “Right to Work Laws and Manufacturing Employment: The Importance of Spatial Dependence,” published in the Southern Economic Journal, argued that studies that attempt to measure connections between right-to-work laws and manufacturing employment (among other sectors) “dramatically overstate the positive relationship between RTW legislation and manufacturing employment.”[13] This is likely due to omitted variables, a common issue raised in reviews of academic papers, whether related to right-to-work or not. They point to the 1998 paper by Thomas J. Holmes and argue that his use of a particular statistical technique known as “Ordinary Least Squares” may have biased his estimates upward.[14]
In their own analysis, Kalenkoski and Lacombe attempt to better control for omitted variables than other previous scholars. They too find positive impacts from right-to-work on manufacturing employment, though smaller ones than did Holmes.[15] They also found that right-to-work “legislation is positively associated with employment shares in the information and professional, scientific, management, administrative, and waste management services industries” but “negatively associated with “agriculture, forestry, fishing and hunting, and mining industries and some service industries.”
In March 2020 the Journal of Financial Economics published “The Economic Impact of Right-to-Work Laws: Evidence from Collective Bargaining Agreements and Corporate Policies.” This study touched on bargaining influences, wages of unionized workers, investment, profits, compensation for executives and changes in employment in five states with right-to-work laws, including Michigan.[16]
Among its many conclusions is that firms increase investments and employment in states after a right-to-work law is adopted.[17] The authors, however, also found a decline in wage growth among workers covered by collective bargaining agreements over a period of about one year.[18]
“The Long-Run Effects of Right to Work Laws,” by Benjamin Austin and Matthew Lilley of Harvard University, is a working paper made public in November 2021 that like this study examines county-level data to measure the impact of right-to-work laws on employment in the manufacturing sector. The authors find that “the manufacturing share of employment is 3.23 percentage points (or approximately 28%) higher on the RTW side of the policy border.” This is similar to the findings of this paper, showing manufacturing employment share in 2018 in border counties to be 21% higher than it otherwise would be in right-to-work states. The Harvard scholars also note that right-to-work is associated with population growth and net commuters from non-right-to-work states, as well as higher labor force participation and lower childhood poverty rates.[19]
Published in 2019 in the Journal of Law and Economics, “Do Right-to-Work Laws Work? Evidence from Individuals’ Well-Being and Economic Sentiment,” examined the passage of right-to-work laws on union workers’ economic sentiment as well as their life satisfaction. The author, Christos Makridis, reports increases in both. As part of the analysis, he compared nonunion and unionized employees before and after passage of a right-to-work law and found, “the positive association between RTW laws and well-being is concentrated among union workers.”[20]
In this research Makridis asked if “measures of well-being and sentiment reflect genuine changes in real economic activity.” Referencing his 2018 working paper, “Sentimental Business Cycles and the Protracted Great Recession,”[21] he writes “a 1-percentage-point rise in employment growth is also associated with a 0.34-percentage-point rise in the probability that an individual reports that their firm is expanding, suggesting that self-reported information about economic sentiment reflects authentic improvements in local economic activity.”[22]
As one of several checks on his analysis of the data, Makridis employed a cross-border analysis, citing Holmes, and comparing well-being between workers in right-to-work states with those in non-right-to work states. He found consistent results doing so, though the economic sentiment “is not statistically significant at conventional levels.”[23]
In 2018 the consulting firm National Economic Research Associates, Inc. updated its work, “Right-to-Work Laws: The Economic Evidence,” an academic literature review focused on economic performance, wage impacts and union density. Some of the research described by NERA is also reviewed here. With respect to the economic development consequences of right-to-work laws, the paper says, “RTW laws directly affect economic performance through their impact on business location decisions, especially in heavily unionized industries such as manufacturing. Other things equal, businesses are more likely to locate in states with RTW laws. There is also evidence that RTW laws have a direct effect on employment, output and personal income.”[24]
The 2017 paper, “Show-Me Right to Work: A Regional Comparison of Right-to-Work and Non-Right to Work States,” measures right-to-work’s impact based on socioeconomic metrics, including quality-of-life ones. The study is focused in on a specific, nine-state region, including Missouri and eight neighboring states.[25] The authors make comparisons between right-to-work and non-right-to-work states using about 60 different measures.[26]
Only 10 of the indicators used demonstrated a statistically significant different outcome between states with right-to-work protections and those without them. Of those, four measured economic impacts. Closely related, however, were four more on business impacts. The remainder involved quality-of-life issues.[27] The authors found that “both household income and wages grew faster in RTW states in the first few years after the recession ended” (in 2009) and that right-to-work states in the region “tended to have a lower share of long-term unemployed.” These were among other findings, not all of which were necessarily positive for right-to-work laws.[28] For instance, the authors found that injuries in right-to-work states happened at rates “slightly higher than in non-RTW states.”[29]
The Oklahoma-specific journal article, “What Do Right-to-Work Laws Do? Evidence from a Synthetic Control Method Analysis,” was published in 2016 in the Journal of Policy Analysis and Management. The authors found adoption of right-to-work in Oklahoma did not lead to an improved employment rate or average wages in the private sector. It did find a decrease in rates of unionization there, however. Narrowing the analysis to just Oklahoma’s manufacturing sector did not change the findings.[30]
The authors note that it is important to remember that Oklahoma had a relatively low unionization rate to begin with, so impacts from adoption of right-to-work there may not translate to states with greater union density.[31] In 1998, the percentage of private union members working in Oklahoma’s manufacturing sector was 6.6%. In Michigan, during that same year, it was 17.5%, according to unionstats.com.[32]
Another 2016 study of right-to-work laws was published by the Cato Journal and titled “New Evidence on the Effect of Right-to-Work Laws on Productivity and Population Growth.” The three authors — Michael J. Hicks, Srikant Devaraj and Michael LaFaive — have all published work for the Mackinac Center for Public Policy and the latter is co-author of this paper. The authors looked at both productivity and population growth in manufacturing and found that manufacturing in non-right-to-work states was only about 64% of that in right-to-work states.[33] The research also found that “the presence of an RTW law boosted state population growth by 1.1 percent to 1.5 percent,” over two time periods, respectively: 1971-1990 and 1991-2003.[34]
In 2014, the Competitive Enterprise Institute in Washington, D.C., published “An Interstate Analysis of Right-to-Work Laws.” The authors measure changes in income in right-to-work states from 1977 to 2012 while controlling for economic phenomena that may also affect personal income growth.[35] The authors then use the data to help answer the question: “What would have happened to income levels over the 35-year period of 1977-2012 in states that did not have an RTW law in 1977 had they, in fact, adopted one by 1977.”[36] They estimated that most non-right-to-work states lost per-capita income between $2,500-$3,500. That is, per-capita incomes in non-right-to-work states would be as much as $3,500 higher today. The median figure, according to the authors, was $3,278, which translates into a loss of income of $13,000 for a four-person family annually.[37]
Michigan ranked 10th worst among the 30 non-right-to-work states in this study, authored by Richard Vedder and Jonathon Robe, with $3,460 in per-capita income losses.[38] The authors described this impact for the Great Lake State for the period of their study, writing:
In 1977, Michigan’s per capita income was 7.4% above the national average; by 2012, it was some 12.2% below the national average. According to the statistical estimation in Table 1, about two-thirds of the current deficiency in Michigan’s actual per capita income relative to the national average would have been eliminated if it had an RTW law. In 1977, Michigan had 14.5% higher income per capita than RTW Texas. By 2012, by contrast, income per capita was more than 10% higher in Texas than in Michigan.[39]
[*] The review necessitated sifting through many research articles to winnow the list to those that would best inform our research. The list of studies described below is not comprehensive. Our broad research began by sifting through more than 1,000 links to subject-specific academic studies using Google Scholar and refining that search from there.