Breastfeeding laws and breastfeeding practices by race and ethnicity.OBJECTIVES:  We sought to examine breastfeeding practices by race and ethnicity in areas with and without eight specific breastfeeding laws. METHODS:  The 2003 through 2010 National Health and Nutrition Examination Survey provides national breastfeeding practice information. We assessed eight breastfeeding laws before and after legislation was enacted and linked to population-based estimates of breastfeeding initiation and duration for children between birth and age one. FINDINGS:  Relative to Whites, Mexican-American infants were 30% more likely to breastfeed for at least 6 months in areas with laws protecting break-time from work to pump, and 20% more likely to breastfeed for at least 6 months in areas with pumping law enforcement provisions. Unexpectedly, five laws with the intention of supporting breastfeeding duration were significantly less helpful for African-American women relative to White women. African-American women were nearly half as likely to breastfeed for at least 6 months, relative to Whites in areas with provisions to provide break-time from work (adjusted odds ratio [AOR], 0.6; 95% confidence interval [CI], 0.5-0.8), private areas to pump at work (AOR, 0.6; 95% CI, 0.4-0.8), exemption from jury duty (AOR, 0.6; 95% CI, 0.4-0.9), awareness education campaigns (AOR, 0.5; 95% CI, 0.3-0.8), and pumping law enforcement provisions (AOR, 0.6; 95% CI, 0.5-0.8). CONCLUSIONS:  Breastfeeding laws influence African Americans and Mexican Americans differently than Whites. Examination of specific laws in conjunction with the interaction of known specific barriers for African-American mothers could help to achieve the Healthy People 2020 goals for breastfeeding.