Nicola Sacco and Bartolomeo Vanzetti were Italian immigrants and anarchists, controversially accused of murdering Alessandro Berardelli and Frederick Parmenter, a guard and a paymaster, during the April 15, 1920, armed robbery of the Slater and Morrill Shoe Company in Braintree, Massachusetts, United States. Seven years later, they were executed in the electric chair at Charlestown State Prison. Most historians consider their conviction unfair due to prejudice against immigrants and radicals.