An OTI Experiment: Open Source Surveillance Detection

The Open Technology Institute team did a technical experiment at this Spring’s March for Science in Washington (DC) to try and answer these questions and explore new ways of detecting when your cell phone is being surveilled. The increasingly broad use of cell site simulators by law enforcement is controversial for many reasons. As a general matter, the devices themselves indiscriminately invade the privacy of everyone around them because they connect to, and can capture data from, all phones within their range. But the devices have also been used in controversial ways. In particular, they have been deployed disproportionately in areas made up predominantly of people of color.

We decided to conduct an experiment to see whether and how one might be able to detect the use of cell site simulators during a large protest. In particular, OTI conducted a spectrum survey at the March for Science in April 2017 to experiment with ways to identify these devices. Although our results were inconclusive, they gave us new insights into how best to tackle this problem, insights that we and others can apply to future experiments with the same goal: developing tools that give us the power to watch the watchers.