Gunshot Detection Inside Schools - Useful Or Useless?

ShotSpotter has had some considerable press over the last few days about its new solution for indoors, mainly targeted at schools. They say it can detect the location of shots fired in a building. A charter school in Oakland will be the first to install the system.

On its outdoor installations it uses microphones. Its indoor installations will use some sort of sensor: "A sensor about the size of a light switch will be placed in every room in the school, including open areas and hallways. The sensors are designed to detect the pressure changes and infrared heat associated with gunshots," according to the San Franciso Chronicle.

The cost for ShotSpotter's indoor solution: $15,000 installation and $10,000/yr

To put things in some perspective, here are some stats that show the risk of gun violence:

Since 1987, 297 people have been killed in school shootings. In 2011, five percent of students reported carrying a weapon (a gun or otherwise) on them at school and five percent of students reported having access to a loaded gun during the school year.

But how much impact would this technology have had in any of those if it doesn't kick in until someone starts shooting.