Progressive Era reformers believed that women workers needed to be protected from the hazards of industry because women were mothers. These reformers defined motherhood broadly, maintaining that a mother's duties included caring for and rearing children and maintaining safe, moral, and healthy households. Maximum-hours limits and prohibitions on night work were intended to protect working women from being too fatigued to perform these duties. In Muller v. Oregon, the U.S. Supreme Court upheld gender-specific protection laws, justifying the state's role in this arena by asserting it was in the public interest “to preserve the strength and vigor of the race” (p. 23).