About ten o'clock a platoon of police marched to the Square, halted a short distance from the wagon where the speakers were, and an officer commanded the meeting to immediately and peaceably disperse.

Thereupon a bomb was thrown from near the wagon into the ranks of the policemen, where it exploded, killing and wounding a number.
The man who threw the bomb was never positively identified, but it was probably one Rudolph Schnaubelt, who disappeared.

At all events, the condemned were not connected with the actual throwing; they were convicted upon the theory that they were co-conspirators with him by reason of their speeches, writings, and conduct which influenced his conduct.
An even broader doctrine of liability is announced in the following paragraph from the opinion of the Supreme Court of Illinois: "If the defendants, as a means of bringing about the social revolution and as a part of the larger conspiracy to effect such revolution, also conspired to excite classes of workingmen in Chicago into sedition, tumult, and riot, and to the use of deadly weapons and the taking of human life, and for the purpose of producing such tumult, riot, use of weapons and taking of life, advised and encouraged such classes by newspaper articles and speeches to murder the authorities of the city, and a murder of a policeman resulted from such advice and encouragement, then defendants are responsible therefor." It is the logical application of this proposition that will defeat the "propaganda of action." If it be enacted that any man who advocates the commission of any criminal act, or who afterwards condones the crime, shall be deemed guilty of an offence equal to that advocated or condoned and punished accordingly, the "propaganda of action" in all branches of criminal endeavor will be effectually stifled without the doubtful expedient of directing legislation against any particular social or economic theory..