There are some taxi companies that employ a system whereby a taxi driver belonging to any of the companies turns on the crime-prevention switch, the wireless equipment sends the taxi's current positional information and a distress signal to the wireless office, and the taxi's radio becomes always-on state so that the conversation in the taxi can be heard by people in the wireless office.
無線機器が連動して、防犯ONにすると自動的に車両の位置情報と救難信号が送信され、無線のマイクがつなぎっぱなしとなり、車内のやり取りが無線室に聞こえるシステムを採用している会社もある。