During the first half of the 20th century, many states passed labor laws in response to the influx of women into the modern workplace. The so-called protective labor laws enacted by U.S. states restricted women's economic opportunities through maximum hours restrictions, minimum wage laws and nightshift bans until the civil rights reforms of the 1960s ended these laws on the basis of gender discrimination.
New research led by economist Matthias Doepke at Northwestern University seeks to understand why these laws were introduced in the U.S. during this period, and what led to their overturning decades later.
The study is the first to analyze protective labor laws using a political economy model. It is also the first to compare the model to state-level evidence in the U.S. The researchers looked at when each law was passed and who was voting at the time. They paid special attention to the share of voters who were men with little job training who might feel like they were competing with women for work, and sole-earner couples including such men. They also looked at other indicators that might help explain the laws.
Because advances in women's rights are closely linked to successful economic development, the study coauthors found the era of protective labor laws interesting because it temporarily reversed progress toward gender equality in the U.S. that had been underway during the previous 150 years.
"Despite the name, the main driving force behind the introduction of so-called 'protective labor laws' was men's desire to be protected from labor market-competition, rather than an attempt to protect working women from harm," said Doepke, the Gerald F. and Marjorie G. Fitzgerald Professor of Economic History at Northwestern and senior author of the study.
"While advances in workplace safety laws for both women and men may have been a direct result of these laws, overall, we regard these laws as a form of labor-market discrimination that is best left behind," Doepke said.
Key findings
While the laws were framed as measures to protect women's health and prevent exploitation, the authors sought to examine other motives for advocating for reform.
The researchers used formal models (mathematical modeling for how people form families, participate in the labor market and how this shapes their political preferences regarding protective legislation) in combination with empirical analysis of state-by-state variations in these laws.
The biggest factor they found in bringing about the era of protective legislation was an evolution from gendered division of labor typical to family-based agriculture labor, to increased participation of women in the modern workforce, which put women and men into competition for the same jobs in factories and offices.
They also found the main force behind the reversal of these laws was the increase in married women in the workforce. As soon as most men were married or expected to be married to a woman who also was working, restrictions on women's work would have run counter to their own goals and lost favor.
Doepke said the study results suggest two factors were key to driving the advancement of gender equality: high marriage rates combined with high labor force participation among married women.
"This combination is powerful because it implies that most women and men ultimately benefit from gender equality, because most can expect to be part of a household that relies on the income of both a working man and a working woman," Doepke said.
Implications
The study is timely today, because of the declining marriage rate, the authors said.
"Today many people never marry, and this is particularly true for less-educated individuals. This implies, specifically, that young men are on average less vested in gender equality today," Doepke said.
"I think this is one of the forces behind the rising divide between young women and young men, with young men turning more conservative and being less supportive of gender equality than earlier cohorts."
"Protection for Whom? The Political Economy of Protective Labor Laws for Women" was published by the National Bureau of Economic Research in April 2025.
Co-authors include Hanno Foerster, assistant professor of economics at Boston College; Anne Hannusch, assistant professor of economics at the University of Bonn; and Michèle Tertilt, professor of economics at the University of Mannheim.
