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Creating a ‘Fire Alarm’ for Terror Attacks

November 23, 2015

Technologies like ShotSpotter can help pinpoint exact location of gunshots, explosions

As the attacks on Paris, Beirut, Mumbai, Mali, Kenya and elsewhere demonstrate, we live in a world in which law enforcement must constantly be on guard. Far too many of us will at some point be forced to react when preventive measures fail.

Metropolises like New York City and London have created elite antiterrorism rapid response teams, but there is a problem—how can authorities know, as quickly as possible, that an attack is under way?

In the U.S., the nature of the 911 system can lead to significant delays in understanding what is going on in a Paris-style attack. First, those who are closest to the event are the least likely to call, since they are probably running and seeking cover. Those who do call are at a remove, and so may not know the precise location or nature of the attack. Then there are the mechanics of a 911 call itself—dispatchers attempting to extract information from frantic callers, the time it takes a call to be escalated, etcetera.

But there is a better way, says Ralph Clark, president and chief executive of SST Inc. For nearly 20 years, his company has been perfecting a technology called ShotSpotter, which has been rolled out in 90 cities, towns and suburbs world-wide. It uses Internet-connected microphones to pinpoint, through triangulation, the exact location of a gunshot or explosion.
“What we can provide is a total awareness point of view on outdoor shootings,” says Mr. Clark. Authorities are alerted within 30 to 45 seconds of the first shot in an attack, he adds, as opposed to the minutes it can take to pinpoint an attack using conventional means.

To date, the expense of rolling out ShotSpotter has meant that it has only been used to cover areas of high gun crime—a few square miles within a typical city. But thanks to the usual forces of miniaturization and falling prices, plus a recently announced deal with General Electric Co. GE 1.29 % , ShotSpotter will soon be capable of covering entire cities, says Mr. Clark. The key, believe it or not, is street lamps. GE has been pushing its “smart cities” gear hard, arguing that as long as cities are updating old-style streetlights to LED lights to save money on electricity and bulb replacement costs, they might as well opt for models that are also laden with sensors suitable for tracking everything from traffic to air quality.

When ShotSpotter started talking to GE, says Mr. Clark, he was surprised that GE’s smart streetlights already had everything on board required to become ShotSpotter sensors—save ShotSpotter’s software and an inexpensive microphone. “A typical European city doesn’t have gun violence” on a regular basis, says Mr. Clark. “But what they are increasingly more concerned about is a Mumbai-style attack.”

ShotSpotter works by listening all the time, using machine learning algorithms to discriminate between gunfire and ambient noise. Precise time- and location-stamped data is sent to servers in the cloud that can use this data to figure out exactly where a sound comes from, as long as it is picked up on at least three microphones. Thus, a technology originally developed to help police respond to and reduce the amount of gun violence in America’s inner cities now has the potential to be deployed all over the world to cope with a very different kind of gun violence.
“We can’t prevent a Mumbai-style attack with this technology, but what we can do is be a very fast, precise alarm to mitigate the downstream consequences of an active shooter scenario,” says Mr. Clark, who calls the system a “fire alarm for gunshots.”

As long as we are talking about covering cities, what about the entire globe? That is one thing David Bray, in his role as an executive in residence at Harvard University, has been thinking about as he contemplates parallels between the attack in Paris and what he saw in Afghanistan, where he was a special adviser for the North Atlantic Treaty Organization’s International Security Assistance Force.

Why wouldn’t it be possible, he told me, to use the microphones on all the cellphones everyone is carrying around to create a ShotSpotter-like system that anyone could opt into? After all, we already have cellphones that listen all the time—for activating phrases like “OK, Google”. And with the advent of “beacons” our phones will soon be able to locate themselves in space with centimeter accuracy, even indoors.

Of course, creating such a system would require the cooperation of the public and companies like Google Inc., which didn’t respond to a request for comment, and Facebook Inc., FB 1.00 % which declined to comment. But Facebook’s “Safety Check” system, which was instrumental in communicating about the fate of Parisians immediately after the attacks, suggests there are ways to stitch all of our mobile technology into an inexpensive, flexible and ubiquitous early-warning system for terrorism.
Getting there won’t be easy, warns Mr. Bray, and could require public-private partnerships of the sort that have worked for creating, for example, self-driving cars.

Concerns about privacy aside—any such system would have to be completely open-source so that security experts could probe its potential for misuse—it is hard to contemplate living in a world in which we are asked to digest fresh atrocities seemingly every week without at least talking about how we might use the technology in our pockets to mitigate their horrific effects.

Wall Street Journal