Did Cape Town’s gunshot detection system work? Why jury is still out on what ShotSpotter achieved

By Grant Oosterwyk, Ojelanki Ngwenyama and Raffaele F Ciriello

In mid-2026 Cape Town’s city council ended the use of ShotSpotter, a US-developed gunshot detection system and a form of dragnet surveillance. The system was first piloted in 2016. The council said it was reviewing a renewal of the contract. The acoustic system was marketed as being able to detect and alert police officers to gunfire within 60 seconds.

Information systems researcher Grant Oosterwyk and his colleagues unpack a recent paper that raises questions about accountability, commercial interests and community participation in the context of surveillance technology.

What is dragnet surveillance?

People often imagine surveillance as targeted: police following a suspect or gathering evidence in a specific investigation.

Dragnet surveillance works differently. It monitors a whole area rather than a particular person. Examples include city-wide CCTV networks, automatic number-plate recognition, bulk communications monitoring and acoustic sensors that listen for possible