Source: The Conversation – Africa (2)
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 gunfire.
Instead of beginning with an individual suspect, dragnet surveillance begins with a location. People are monitored because they live, work, or move through an area covered by the system. Surveillance of an individual normally requires some justification, and often judicial authorisation. Dragnet systems require none: everyone within range is monitored, whether or not they have done anything wrong. And some neighbourhoods live under permanent monitoring; others never do.
South Africa’s constitution protects privacy, and laws regulate the processing of personal information. But the issue is also power: who decides where surveillance is deployed, how it is evaluated and how affected communities can influence its use.
What is ShotSpotter?
ShotSpotter is an acoustic gunshot-detection system developed by the US company SoundThinking. Sensors placed on buildings or poles detect sounds that may be gunfire. When several sensors detect a possible gunshot, the system estimates its location and sends an alert to police.
The technology is used most widely in the United States, where SoundThinking says it operates in more than 180 cities and communities.
Cape Town first piloted ShotSpotter in Hanover Park and Manenberg in 2016. These are settlements on the Cape Flats where families were forcibly resettled under racial laws in the 1960s and 1970s.
The project was stopped in 2021 due to budget constraints, then revived and expanded, also to apartheid-era settlements. This formed part of the city’s broader investment in technologies like CCTV, drones and aerial surveillance.
The investment responds to a severe problem. Cape Town has among the highest murder rates in South Africa. Cape Flats communities accounted for roughly three-quarters of murders recorded in the Cape Town policing district in the first nine months of 2025. Gang conflict drives much of it. Of 242 gang-related murders recorded nationally in one quarter of 2025, more than 90% occurred in the Western Cape province. Policing capacity is stretched, so technology that promises to pinpoint gunfire is politically attractive.
City of Cape Town reports suggest that the system was useful. In the 2024/25 financial year, ShotSpotter logged 3,893 alerts and 9,223 rounds fired, about 30% lower than the year before. Between April and June 2025, more than half of all firearms recovered by city enforcement agencies were in areas covered by ShotSpotter.
But there has not yet been an independent public audit of the system’s accuracy, false alerts, response times, or effects on policing outcomes.
The public doesn’t know whether it reduced gun violence.
Why is it controversial in Cape Town?
At first glance, the case for ShotSpotter is straightforward: faster gunfire detection could help police respond more quickly, and might save lives. The controversy is not about whether detection can ever be useful, but about evidence, placement, and how violence is framed.
First, the evidence is contested. In the US, ShotSpotter has faced scrutiny from public oversight bodies independent of the police. A court found that fewer than one in ten alerts produced evidence of a gun-related crime; Chicago cancelled its contract in 2024.
Our recent study argues that Cape Town imported not only the technology but also the language promoting it, without independent scrutiny. In the US, that scrutiny came from institutions independent of both police and vendor: inspectors general, an elected comptroller, and courts.
Cape Town has no standing equivalent for policing technology. The city assessed its own programme largely using data generated by the supplier. An independent evaluation could have come from the auditor-general of South Africa, which audits municipal performance; from council oversight committees commissioning external review; or from researchers granted access to the raw alert data. None was published.
Second, placement. The system is concentrated in poor, working-class areas shaped by apartheid spatial planning. Are these communities being better protected, or simply more closely monitored, with little say in how the technology is governed?
Third, our research found a gap between official and community framing. Officials and vendors speak of precision, rapid response and smart policing; residents speak of fear, trauma, unemployment and mistrust of police.
There is also opportunity cost. Money spent on surveillance is money not spent on the conditions that drive violence. The central question is who decides that surveillance comes first.
What needs to happen?
First, Cape Town needs independent audits. Claims about accuracy and effectiveness should be tested by bodies with no financial or political stake in the system.
Second, scrutiny should happen before and during deployment, not only after controversy emerges. A review should ask whose definition of safety a technology encodes, which institutions it assumes exist and whose knowledge it treats as authoritative.
Read more:
Smart cities start with people, not technology: lessons from Westbury, Johannesburg
Third, affected communities should have a stronger voice. Residents and community organisations should help define what safety means, how impact is measured and what safeguards are needed.
Finally, detection is not prevention. Sensors may identify where shots were fired, but they cannot explain why violence persists. Lasting improvements in public safety require investment in the social conditions that shape violence, including unemployment, trauma, weak social infrastructure, illicit firearms and strained trust between residents and police.
The central question is whether a surveillance system strengthens public accountability, community safety and democratic trust.
The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.
Original source: https://analysis1.mil-osi.com/2026/07/30/did-cape-towns-gunshot-detection-system-work-why-jury-is-still-out-on-what-shotspotter-achieved/