Automatically recorded images of shoppers' faces taken by security cameras have been shared among 115 Japanese supermarkets and convenience stores as an anti-shoplifting measure, without customers' knowledge.
Although the images are used mainly to prevent shoplifting, experts and industry bodies say it is necessary to make clear rules because providing people's facial data to a third party could constitute an invasion of privacy.
The facial data in question was shared by 115 stores of 50 separate operators that have installed a shoplifting prevention system that a Nagoya-based software development company had started marketing in October of last year.
The stores include major convenience stores operated by individuals under franchise contracts. At these shops, security cameras film all customers' faces. If a person shoplifts or makes an unreasonable complaint at one of the stores, security camera footage of the person is processed into facial data with the recognition system and classified into categories such as "shoplifter" and "complainer".
They are then sent to the software firm's server to be recorded. The facial images themselves, however, cannot be browsed from other stores.
Once registered on the digital blacklist, however, a warning is issued to the staff of other stores - in a way only the staff can notice - when the face-recognition system installed at these stores detects the blacklisted person visiting their stores. At these stores, stickers are placed within the stores to inform customers that "face recognition security cameras are installed". But customers are not informed that the stores are sharing the facial data.
Under Japanese law, facial images that are filmed by security cameras are considered personal information. The law allows such images to be filmed when it is used for crime prevention.
But sharing the facial data could be a violation of a law that bans providing personal information to a third party without the person's consent.
Lawyer Yoichiro Itakura said the data could be used in a way disadvantageous to customers as "stores can arbitrarily register specific shoppers as suspicious people, and they may then suffer unjust treatment at stores they have never visited before".
An official of the Nagoya software development firm said: "The system has no problems. We just responded to the needs of the stores, which is their need to prevent shoplifting."