The Fugitive Slave Act of 1850 upset residents of Northern states because it required them to assist in the capture and return of runaway slaves, even if they were living in a free state. It also allowed slave owners to pursue their runaway slaves into free states and territories, and gave them the right to a jury trial to determine if the person was a runaway slave. This was seen as a violation of the rights of free states and territories, and a violation of the rights of the runaway slaves.
