
Margaret Morgan, born into slavery in Maryland, had been living with her husband and their children in the free state of Pennsylvania for five years when hired slave catchers led by Edward Prigg seized them one night in 1837, and hauled them away in “an open wagon in a cold sleety rain, with scarcely their ordinary clothes on.”
Their case was examined by the U.S. Supreme Court in Prigg v. Pennsylvania, which said slavery was so fundamental to the nation's formation that the rights of slave owners to “this species of property” could not be limited. The 1842 ruling is among the slavery law precedents directly cited more than 7,000 times in American jurisprudence, according to the Citing Slavery Project at Michigan State University.