On May 4, 1886, socialist and anarchist labor activists assembled at Chicago's Haymarket Square during the bitter campaign for an eight-hour workday. When police ordered the gathering dispersed, someone hurled a bomb into their ranks. Chaotic gunfire followed. Eight Chicago police officers ultimately died from injuries attributed to the attack: Mathias J. Degan, John J. Barrett, George F. Miller, Timothy J. Flavin, Michael Sheehan, Thomas Redden, Nels Hansen, and Timothy Sullivan. Fifty-nine other officers were wounded. August Spies, Albert Parsons, Adolph Fischer, and George Engel were convicted of murder under conspiracy and accomplice-liability theories and hanged on November 11, 1887. Louis Lingg killed himself the previous day. The unidentified bomber was never tried, and none of the executed men was proven to have thrown the bomb. Were they hanged for speech? Technically, no. They were convicted of murder based on an alleged conspiracy to promote and encourage revolutionary v...