Southern slave owners responded to slaves’ attempts to escape north by passing the Fugitive Slave Act in 1850. The Act stated that fugitive slaves could not testify on their own behalf and could not have a trial by jury. It also stated that all U.S. marshals, including those in the North, had to assist in the capture and return of escaped southern slaves, and that citizens should also aid in the capture of runaways. Individuals who helped slaves escape now faced very harsh punishments. The passage of this act terrified many former slaves, who had assumed they were safe after escaping to the North but now wondered if every stranger they passed on the street would try to return them to bondage.
"The last thing that remained to be done to complete this hell on earth was done in 1850, in passing the Fugitive Slave Law. There is not a State, a city, nor a town left as a refuge for the hunted slave; there is not a United States officer but what has sworn to act the part of the bloodhound in hunting me down, if I dare visit the land of Stars and Stripes, the home of the brave, and land of the free. Yet, according to the American declaration of independence, it is a self-evident truth that all men are created by their Maker free and equal, and endowed with certain inalienable rights--life, liberty, and the pursuit of happiness. Where are the coloured man's rights to-day in America?"
However, the majority of Northerners were unsympathetic to slavery and the troubles of slave owners. They either ignored the Fugitive Slave Act, or were so angered by it that they increased their efforts toward abolition and assisting escaped slaves via the Underground Railroad. Several Northern states passed personal-liberty laws in response to the act, guaranteeing fugitive slaves a jury trial and preventing harsh punishments against those who assisted escaped slaves. This conflict over the Fugitive Slave Act increased the growing tension between the North and South in the years leading up to the Civil War.