Do CCTV Cameras Actually Deter Crime? What the Evidence Says

What does the research actually show?

The most cited evidence base — systematic reviews by Welsh and Farrington and the later Piza et al. meta-analysis of 76 studies — found consistent overall reductions in crime in areas with CCTV, with the strongest effects in car parks and residential settings, and for drug, vehicle and property offences. Effects on violent and spontaneous crime are much weaker: someone who hasn't planned an offence doesn't do a cost-benefit calculation about cameras.

Why do burglars avoid camera-covered properties?

Interviews with convicted burglars repeatedly rank visible CCTV among the top deterrents alongside alarms, dogs and signs of occupancy. Burglary is mostly opportunistic target selection between similar properties — the house or unit with visible cameras, an alarm bellbox and good lighting simply loses the comparison. Deterrence is relative: you don't need to be uncrackable, just a worse bet than the alternative.

How to make CCTV deter, not just record

• Make cameras visible at decision points: gates, entrances, approach routes — deterrence happens before entry
• Add signage: it amplifies the deterrent and is legally required for business systems anyway
• Keep cameras obviously alive: dangling cables and tilted dead cameras advertise neglect
• Pair with lighting: cameras imply watching; lighting removes the cover burglars need
• Use active deterrence where it fits: cameras with strobe and audio warning on detection measurably interrupt intrusions on sites and yards