The Justice Ministry is considering attaching GPS trackers to inmates at four open-type prisons following the recent escape of a convicted thief from one of them, said a source close to the matter Wednesday.
The idea of using GPS data to monitor inmates was presented at a meeting of the ministry's committee tasked with discussing preventive measures, after 27-year-old Tatsuma Hirao ran away from Matsuyama Prison's Oi Shipyard in Imabari, Ehime Prefecture, on Sunday evening. He is still on the run.
The committee will soon draw conclusions on how to best monitor inmates at such prisons, which are without perimeter walls and are meant to promote the inmates' early return to society by allowing them to live in a more ordinary environment.
At the Ehime prison there have been six escapes, including the latest, since 1989. But there have been no escapes at the other three open-type prisons in Hokkaido, Chiba and Hiroshima.
When deciding on a suitable form of surveillance at such facilities, "it's also necessary to compare (measures taken at) the facilities. We want to also look at intangible elements such as human relationships within each facility," a senior ministry official said.
Monitoring using GPS technology has already been introduced at four other prisons in Japan, including one in Kagoshima, since fiscal 2012, according to the ministry. Prisoners wear GPS devices when they go outside of the prisons to work.