In a bold move to placate Southern slave owners, the U.S. Congress passed the Fugitive Slave Act of 1850, forcing Northern states to assist in capturing and returning escaped slaves to their owners. The law sparked outrage among abolitionists and strengthened the anti-slavery movement, as many saw it as a cruel and unconstitutional attack on personal freedom. The Act also created a flurry of "slave catchers" who received bounty for capturing suspected runaways, often using dubious methods to identify their prey. This highly divisive law ultimately contributed to the growing tensions leading up to the Civil War.