Charged with enforcing the law, Palmer trampled the Constitution instead. With the Bolshevik Revolution stoking fears over the spread of Communism, Palmer—using the 1917 Espionage Act and 1918 Sedition Act as justification—engineered the mass-arrest of left-wing individuals, dissidents and foreigners. He detained some without charge and deported others. Though Palmer meant to combat Communism, he instead helped usher in the civil liberties movement. The ACLU was formed partly in response to the "Palmer Raids."