[johncarpinelli]

An automatic gun defense device like a smoke detector that is cheap and ubiquitous. The device should cost $100-$200 and could be installed in schools, shopping malls, cinemas and street lamps.

If the device detects a gun-shot, it locates the shooter through triangulation of the sound and image recognition. Non-lethal defenses would be deployed automatically to prevent continued shooting: e.g. stun grenade/flashbang, tear gas, electric shock. After detecting a gun-shot, the device would record audio/video and call 911 automatically. The shooter's escape could be tracked through a network of the devices.

http://en.wikipedia.org/wiki/Electroshock_weapon#Wireless_lo...

[jauer]

Shot spotter (http://www.shotspotter.com/) does the detection aspect of this.

A low-cost clone might not be feasible due to patents: http://www.shotspotter.com/patents

[paulgerhardt]

I spend a fair amount of my time in Oakland where I hear gunshots about as frequently as I see car accidents.

Everytime it happens the first thing the neighbors do is hop on the local listserv and literally triangulate the source of the shooting based on where they heard the sound coming from, with respect to each other.

A publicly accessible / open source / subsidized / non-locked down / crowd sourced version of ShotSpotter would make a lot of sense. I would hope for something more along the lines of a Safecast[1] for gunshots. If one can cross-correlate with traffic footage it should have a chilling effect. That the ShotSpotter system is locked down and costs ~$4,166.66 per sensor is madness [2].

[1] http://blog.safecast.org/

[2] http://www.wired.com/wired/archive/15.04/shotspotter.html

[jbeldock]

Hi, gang. James from ShotSpotter (SST, Inc.) here. The availability and price of our technology is dramatically (like an order of magnitude) lower than it used to be. The Wired article was accurate at the time, but its pricing data is now way, way out of date. Also, about automated responses: believe it or not, even in the case of a school shooting, it still takes about 3-4 minutes for a call to 9-1-1 to deliver enough information for emergency responders to get the information they need. That's probably the vector for the most meaningful improvement in response time. We're looking at this very closely.

[johncarpinelli]

A low-cost clone could be mounted on the ceiling in a room. Some stun grenades and tear gas would disable the shooter anywhere in the room. This would be a cheap solution. Include a wireless mesh network connecting the devices, and they could disable the shooter even as he flees the first room.

[jauer]

I think the detection and logging aspect has a lot of promise as a cheap and widely deployed system.

I'd worry about the liability from false positives with a active response system. Even something as limited as locking the doors to a room to contain the shooter could lead to liability from someone being trapped with the shooter.

If you assume a large indoor setting, something like a mall or school, maybe combine the detection network with a evacuation guidance system that leads people away from the incident. Mass shootings are pretty rare so maybe you could use it as a general "smart evacuation" system. OTOH there's probably a crowd psychology problem in there that makes that unfeasible.

[johncarpinelli]

Good point about false positives. The device could upload images to a human operator who would activate the defenses. This would add some reaction time, but it would reduce the potential for false positives.

If the device has image recognition to detect firearms being brandished, the operator could trigger the defenses before the first shot is fired perhaps.

[Jayschwa]

This is the first suggestion I've seen that made me go, "Cool!". Mostly because it doesn't involve trying to graft some crazy scanner/computer/tracker onto a gun, which is impractical.

There'd probably have to be someone actively monitoring detections so that car backfires and fire crackers don't create false positives.