Jinka (suspected arson) (神火)
Jinka refers to suspicious fires which often happened from the late 8th century to 10th century, mainly centering on kanga (government office) in Togoku (the eastern part of Japan, particularly Kanto region).
In the imperial decree on September 1 in 763, recorded in "Shoku Nihongi" (Chronicle of Japan Continued), it is written that 'there were many deaths by plague and droughts. Jinka often happened and destroyed lots of kanmotsu (tribute goods paid as taxes or tithes).
This was because provinces' gunji (a local government official) did not respect gods' (Original in Chinese.)
At first, it was thought to be of unknown cause and be a divine punishment a natural disaster, but there were many damages of public facilities such as shoso (public repository) or provincial monasteries of kokuga (provincial government offices) or gunga (provincial office), and in order to prevent financial damages of shozei (the rice tax stored in provincial offices' warehouse) and kanmotsu by destruction in a fire, the risk management by kokushi (provincial governors) and gunji (district managers) were pursued and sometimes they were discharged, recompensed the damages and so on. Furthermore, such incidents came to often happen and they began to think that, behind those incidents, there were political wars in provincial units, concerning positions of government officials such as gunji and so on, or intentional concealment efforts of absence of shozei payment or illegal confiscation of kanmotsu. For this reason, when Daijokan (Grand Council of State) received a report of jinka, they made government officials in Gyobusho (Ministry of Justice) investigate the spot and find the culprit, and the arsonist was sentenced to be kakusatsu (beaten to death), or in the case of hereditary status, it was sentenced to be discontinued.
And jinka happened especially centering on Togoku during the period of the subjection of indigenous inhabitants in eastern Japan, and for Tei MORITA, military and economical burdens became heavy in Togoku because of the subjection of indigenous inhabitants in eastern Japan and the political dissatisfaction made such incidents happen as one factor, and kokushi became zuryo (provincial governor) and thus the relation between kokushi and gunji changed, which is assumed to have been the cause of decrease of jinka incidents.