What was the Alien Act? It authorized the arrest and deportation of immigrants who criticized the government. It limited the fed
eral government to powers explicitly granted by the Constitution. It declared the Sedition Act unconstitutional and hinted that the states had the power to nullify federal laws. It allowed juries to acquit defendants who could prove the literal truth of their statements.
The Alien Act authorized the arrest and deportation of immigrants who criticized the government, since in this case "Alien" refers to those born outside the US.
Mainly because it toughened-up the Fugitive Slave Act, allowing official slave-catchers to hunt down runaways. This recruited many new Abolitionists, and caused Harriet Beecher Stowe to write 'Uncle Tom's Cabin'.
