In late 1992, John Lahr, a seismologist at a nearby US Geological Survey station, who lived in Menlo Park, set up a grid of audio sensors to locate the source of gunshots to within 20 or 30 meters by triangulation and time lapse, thus enabling the Menlo Park Police to pinpoint the location of crimes involving firearms and respond far more rapidly.
In 1994, Robert Showen PhD, an acoustics expert employed by Stanford Research Institute in Menlo Park, adapted Lahr's technology and software and founded ShotSpotter, a company located in Newark California, across the Bay from Palo Alto, that designs and installs acoustic grids to identify and triangulate the location of gunfire within a high crime area of a municipality.
ShotSpotter has installed grids in over sixty US cities, including Miami, Omaha, Kansas City, Milwaukee, Boston, and Washington DC. A few days ago, Mayor Bill de Blasio of New York announced the 1.5 million dollar expansion of a ShotSpotter pilot program, currently active only in the Bronx, to include other "high crime" precincts in New York City.
The problem is that ShotSpotter microphones, mounted on utility poles, are also capable of recording human conversations. In 2014, the Oakland California Police arrested Arliton Johnson for murder based on evidence gleaned from the victim's dying words recorded by a ShotSpotter microphone.
The Constitution of the United States does not, contrary to popular belief, guarantee privacy. It does, however, in Article IV of the Bill of Rights, guarantee that, "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures , shall not be violated,..." Eavesdropping on people on the street would seem to be a violation of that "right of the People to be secure."
Freedom is always threatened by convenience. And the freedom-convenience balance is often a personal decision. Is the convenience of the device on your windscreen that allows you to drive through toll gates without stopping worth providing the government the means of electronically tracking your vehicle?
The answer requires that you know what the risks to your freedom are, and it's up to you to find out. You cannot rely on the government for that information. Prior to the Arliton Johnson case, the Oakland Police Department vehemently assured critics that the ShotSpotter system was incapable of recording human conversation, and the Houston Police Department does not advertise the fact that they can pinpoint the location of the "Easy-Tag" on your vehicle – or that the federal government has that same capability.
The cost of freedom is always inconvenience. It's inconvenient to go to far-off countries to confront enemies foreign who pose a threat to our freedom, and it's inconvenient to confront the enemies domestic who threaten our freedom. But that's the price we have to pay to remain free. Freedom is not a gift bestowed upon us by our ancestors. It is a responsibility they have passed on to us.
"They that can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety." – Benjamin Franklin