Groups of armed men took lands, manors, goods, and women by force. The villeins agreed to assist each other in resisting by force their lords' efforts to return them to servitude. Justices became afraid to administer the law. Villeins, free peasants, and craftsmen joined together and learned to use the tactics of association and strikes against their employers. The office of Justice of the Peace was created for every county to deal with rioting and vagrants. Cooperation by officials of other counties was mandated to deal with fugitives from its justice. When there were attempts to enforce the legal servitude of the villeins, they spread rhymes of their condition and need to revolt. A secret league, called the "Great Society" linked the centers of intrigue. A poll tax for a war with France touched off a riot all over the nation in 1381. This tax included people not taxed before, such as laborers, the village smith, and the village tiler. By this time, the black death had reduced the population from 5 million to 2 1/2 million. It was to rise to 4 million by 1600. Mobs overran the counties around London. The upper classes fled to the woods. But the Chief Justice was murdered while fleeing. Written records of the servitude of villeins were burned in their halls, which were also looted. Prisoners were released from jails. The archbishop, who was a notoriously exploitive landlord, and the Treasurer were beheaded on Tower Hill and their heads were posted over London Bridge. The villeins demanded that service to a lord be by agreement instead of by servitude, a ceiling on rents of 4d. per acre yearly, abolition of a lord's right for their work on demand (e.g. just before a hail storm so only his crops were saved), and the right to hunt and fish. The revolt was suppressed and its leaders punished. Also, the duty to deal with rioting and vagrants was given to royal judges, sheriffs, mayors, bailiffs, and constables as well as the Justices of the Peace. There was a high constable in each hundred and a petty constable in each parish. Justices of the peace could swear in neighbors as unpaid special constables when disorder broke out. The sheriff was responsible for seeing that men of the lower classes were organized into groups of ten for police and surety purposes, and for holding of hundred and shire courts, arresting suspects, guarding prisoners awaiting trial, carrying out the penalties adjudged by the courts, and collecting Crown revenue through his bailiffs. Royal writs were addressed to the sheriff. Because many sheriffs had taken fines and ransoms for their own use, a term limit of one year was imposed. Sheriffs, hundreders, and bailiffs had to have lands in the same shires or bailiwicks [so they could be held answerable to the King]. Efforts were made to keep laborers at the plough and cart rather than learn a craft or entering and being educated by the church. The new colleges at the universities ceased to accept villeins as students.