A groundbreaking study from Northwestern University has revealed that protective labor laws enacted in the early 20th century, intended to safeguard women in the workplace, primarily served to shield men from increased labor market competition. These findings challenge the traditional narrative surrounding these laws and highlight their complex impact on gender equality.
Matthias Doepke, a professor of economics at Northwestern University and the study’s senior author, led a research team that examined the history of protective labor policies across the United States. For approximately 60 years, from the early 1900s to the 1960s, these laws imposed restrictions on women’s employment, including maximum hours of work, minimum wage requirements, and prohibitions on night shifts.
“The main reason these laws were successful indeed was less a need to protect women at work and more a need to protect men from competition,” Doepke stated. “This phenomenon occurred as men and women began to vie for the same job positions in greater numbers.”
Published by the National Bureau of Economic Research in April 2025, the study, titled “Protection for Whom? The Political Economy of Protective Labor Laws for Women,” employs a political economy model and empirical analysis of state-level data. This methodology allowed researchers to explore both the introduction and eventual repeal of these laws. The study was co-authored by Hanno Foerster of Boston College, Anne Hannusch of the University of Bonn, and Michèle Tertilt of the University of Mannheim.
The research indicates that these laws were enacted in response to the growing presence of women in modern workplaces, such as factories and offices, during the early 20th century. This influx marked a temporary reversal of the gender equality progress achieved over the previous 150 years. The laws limited women’s economic opportunities, effectively reducing competition for male workers, particularly those with limited job training in sole-earner households.
The dismantling of these protective laws was significantly influenced by the Equal Rights Movement in the 1960s. Civil rights reforms during this period abolished gender-based discrimination in labor legislation, paving the way for greater workplace equality. Doepke noted that the rise in married women entering the labor force played a crucial role in aligning the interests of men and women, fostering support for policies that ensured equal opportunities.
“When married women entered the workforce in larger numbers, it aligned the interests of men and women more closely, fostering support for policies that ensured equal opportunities,” Doepke explained.
The study also establishes a strong correlation between gender equality and economic prosperity. As women’s participation in the workforce grew in the mid-20th century, support for women’s employment opportunities and antidiscrimination laws increased, contributing to economic growth. Data from the study suggests that high marriage rates and labor force participation among married women were key drivers of this progress.
However, Doepke cautions that current social and economic trends may undermine these gains. Declining marriage rates, particularly among less-educated individuals, and growing political divides between young men and women pose challenges to gender equality. He observed a shift in political attitudes, particularly among young men, who are increasingly adopting conservative views.
“Young women increasingly become more liberal. Young men also used to be liberal but they have started to turn further to the right,” Doepke noted. “For instance, in the recent presidential election, there was notable support for Trump among young men, which reflects differing attitudes on issues like gender equality.”
Recent legal changes and Supreme Court decisions further indicate a potential retreat from commitments to gender equality, making the study’s historical analysis particularly relevant. The research underscores the importance of understanding the motivations behind past labor policies to inform contemporary discussions on workplace equality.
The study’s findings are detailed in a report available through the National Bureau of Economic Research. For additional context, state-level labor laws, such as the Illinois Equal Pay Act, provide examples of modern protections for women in the workplace.
