Microphones detecting Gunshots
If you simply used the microphones inside so many cameras that are installed all over everywhere, you wouldn't need such an expensive matrix. Big Brother is everywhere, glad that SST is working so well. What I don't like is that the state and county and cities don't have the details as to what these gadgets cost. If the people knew, these systems would never have been purchased. It all adds up, maybe that's why California is broke.