Jikendan (voluntary ruling and judging) refers to rural communities in medieval Japan such as soson (a community consisting of peasants' self-governing association) and goson (autonomous village) that conduct a kendan (trial) by themselves. It is sometimes called Jige kendan.
The kendan is the term to mean to rule and to hold a trial, and addressing domestic policies, diplomacies, and governing territories and rural communities were closely connected to holding a trial because security, government, and criminal justice, even the military, were not separated in medieval Japan (according to "Vocabvlario da Lingoa de Iapam:" Japanese-Portuguese dictionary, published 1603 - 1604), kendan was described as a post to rule and hold a trial). Cases on these kendan were called Kendan-sata (criminal cases) in terms at that time and this Kendan-sata included suits and trials against crimes which threatened public order such as murder and injury cases, theft and robbery cases, and coup d'etat.
These rural communities enacted as a legal provision within sosons a clearly-stated so okite (rules) under the agreement of all constituent members and exercised severely their rights to judge criminal cases against those who broke the so okite. Especially, the trials against theft, arson, and murder were harshly punished and many were sentenced to death. Disputes (trouble) between conflicting rural communities were also settled by their own military power and it was usually the case that each community built fortresses at high altitudes and all members had combat training. Sosons and rulers were sometimes in conflict with each other over exercising the right to judge criminal cases but sosons negotiated with rulers and their rights to judge criminals were often confirmed.
It is believed that lords of a manor and public land originally had the right to judge criminal cases. During the Kamakura period, the Kamakura bakufu (Japanese feudal government headed by a shogun) played an central role to exercise the right based upon a delegation from the central government, but lords continued to have the power in principle at least. However, during the Muromachi period, self-governing communities (sosons) by independent peasants were formed and these communities started to exercise the right themselves against Kendan-sata to settle conflicts within the communities and sometimes even between communities. This is the Jikendan. It was a tradition from the preceding era that lords or a Shugo and a Jito (military governor and estate steward) who were delegated from the lords, exercised the right to judge criminal cases even against cases within communities, but with the increased autonomy, communities rejected and excluded the lord's intervention into trials and started to conduct Jikendan themselves.
In the Sengoku period (period of warring states in Japan), ichien shihai (rule the whole territory) by daimyo (Japanese territorial lord) was developed in the Sengoku period and officially Jikendan seemed to disappear and become reduced, however, after the Edo period, authorized communities such as villages and towns (cho) virtually kept possession of their autonomy similar to Jikendan under the compromise and tolerance of the government, standing on the premise that as if they waived their right to judge criminal cases. After the Sword Hunt, keeping arms that supported the right to judge criminal cases as a safeguard military police power had the form of waiving the right and people in a farming rank showed their waiver by not wearing a sword, their rank symbol, but actually an individual community had big stockpiles of swords, spears, and guns under the pretext of dedicating things to Shinto and Buddhist deities or the extermination of harmful animals and the governmental powers could not openly touch them even after the Meiji Restoration.
It was after losing in the World War II when the police succeeded in confiscating and destroying completely these large amount of swords, spears, and firearms, the symbols of the right of Jikendan, under the guise of elimination of militarism and backed by the force and prestige of the occupation forces.