The Fugitive Slave Acts were a pair of federal laws that allowed for the capture and return of runaway slaves within the territory of the United States. Enacted by Congress in 1793, the first Fugitive Slave Act authorized local governments to seize and return escaped slaves to their owners and imposed penalties on anyone who aided in their flight. Widespread resistance to the 1793 law later led to the passage of the Fugitive Slave Act of 1850, which added further provisions regarding runaways and levied even harsher punishments for interfering in their capture. The Fugitive Slave Acts were among the most controversial laws of the early 19th century, and many Northern states passed special legislation in an attempt to circumvent them. Both laws were formally repealed by an act of Congress in 1864.