Among the events in the 1850s that helped drive the nation into civil war, the Christiana Riot put a controversial new law to a bloody test. The Fugitive Slave Act of 1850 ordered federal officers to arrest suspected runaway slaves; it also threatened imprisonment to anyone aiding a runaway. In 1851, Edward Gorsuch, a Maryland farmer, heard that four of his escaped slaves had been seen in southern Pennsylvania. With an armed posse, Gorsuch arrived at William Parker's Christiana home, where fugitives had been hiding. Parker, an escaped slave himself from Maryland, had passed first through York before settling in Christiana. After neighbors gathered to oppose the posse, Gorsuch was shot and killed. Federal authorities charged participants with treason, but all were acquitted. Southerners fumed over the verdict. John Brown's raid on the Federal arsenal in Harper's Ferry, Virginia, lit the country's already short fuse. The Federal force sent after Brown included York resident Lieutenant Michael P. Small. Among Brown's raiders was Osborne Perry Anderson who escaped to Chambersburg on foot. From there he turned to the Underground Railroad for safety. A local conductor, Freedman William C. Goodridge, hid him in York. Anderson eventually escaped to Canada.