I don&#x27;t see this scheme working. It would require a whole bunch of sensors and a chunk of local computing power to make a &#x27;kill&#x27; decision (or at least, an attempt to immobilize) on an individual in a crowded space based on the reliable detection of bullets fired from a gun. The kill device could be disabled prior to discharging a fire-arm, it could trigger falsely, it could be made to trigger falsely on purpose and it could malfunction. I&#x27;m sure that if you pitch this idea to the right party they&#x27;ll shower you with money, nothing like more security theater and false feelings of safety to get big $.