Do Burglar Alarms and CCTV Actually Deter Burglars? What the Evidence Says

"Get an alarm fitted." "Put up some cameras." Both are common suggestions, but neither is a complete security plan. The useful question is what each device can do at the actual property and which physical weaknesses still need attention.

This guide does not assign an unsupported deterrence percentage or rank a particular consumer brand. It uses current Police.uk guidance to separate alarms, cameras and physical door or window security.

What the Research Says About Burglar Alarms

Police.uk's guidance on alarms and CCTV recommends an active alarm as one possible layer and explains that CCTV can be useful but does not prevent crime or replace good physical security. The source does not support the previous uncited percentages or a universal ranking of alarms, dogs, cameras and locks.

What Works: Visible Alarm Boxes

An external box can show that an alarm may be present, but appearance alone does not prove that a system is active, correctly installed or maintained. Choose and use an alarm for its actual operation, not just the box.

What Does Not Work: Neglected Systems

An alarm that is not armed, has unresolved faults or is not maintained cannot be assumed to provide the intended alert. Follow the manufacturer's instructions, test it safely and arrange qualified servicing where required.

Monitored vs Unmonitored Alarms

There are three broad categories:

Bells-only alarms — Sound locally when triggered. Check how the system is armed, silenced, tested and maintained, and do not assume that a neighbour or police response will follow.

Self-monitored alarms — Can send an alert to a nominated device, depending on the product and connection. Check subscriptions, connectivity, battery backup, notification settings and what action the household can realistically take.

Professionally monitored alarms — Send defined events to a monitoring service under a contract. Response arrangements, police eligibility, installation requirements and fees vary, so obtain the current terms rather than assuming that monitoring guarantees attendance.

What About CCTV?

CCTV can record activity within its field of view. It is one layer and must be planned around lawful positioning, usable coverage, storage and household privacy.

CCTV as a Deterrent

The Police.uk source does not assign a reliable deterrence percentage or rank CCTV against other measures. A visible camera must not be presented as a guarantee that an offence will not happen.

CCTV as an Evidence Tool

CCTV may provide footage after an incident, but usefulness depends on positioning, lighting, image quality, time settings, retention and whether the relevant activity is actually captured. It does not guarantee identification, recovery, conviction or an insurance outcome. Know how to preserve and export footage before an incident occurs.

Smart Doorbells

A video doorbell may provide motion alerts, audio or recorded footage, depending on the exact product, subscription, connection and settings. Compare those terms and privacy implications rather than treating one named brand as the best-value choice. It does not replace a suitable door, frame and locks.

What About Dummy Cameras and Fake Alarm Boxes?

A dummy device is not an active alarm or working camera. Do not count it as detection, notification or recorded evidence. If the budget is limited, first assess open, unlocked, damaged or easy-to-force doors and windows. See the lock upgrade and prices page for current physical-security options.

A Layered Security Checklist

There is no universal spending order for every property. Start with the actual weaknesses and household needs:

Priority 1: Doors, Windows and Locks

Check the door, frame, hinges, furniture, accessible windows and suitable locks together. The guide to BS3621 deadlocks explains why the exact door and certification matter.

Priority 2: Lighting and Sightlines

Consider lighting and visibility without creating glare, nuisance or concealed areas. Follow the product instructions and assess the actual approaches to the property.

Priority 3: An Active Alarm

If chosen, use and maintain the alarm. Select bells-only, self-monitored or professional monitoring according to the household and written service terms.

Priority 4: Doorbell Camera

Check the field of view, notification, storage, subscription, connection and privacy implications. It may not record every approach or event.

Priority 5: CCTV

Choose lawful positions and test day and night coverage, timestamps, retention and export. CCTV remains a supplement to physical security.

Priority 6: Monitoring

Compare current contracts, response arrangements and eligibility requirements. Monitoring does not guarantee police attendance or prevent entry.

The Bottom Line

Police.uk treats alarms and CCTV as useful layers while warning that CCTV does not prevent crime or replace good physical security. Check physical openings, then decide which alerting and recording layers suit the property. No device or lock guarantees prevention.

For a property-specific alarm, CCTV and physical-security discussion in Coventry, call 024 7522 4730. The recommendations should follow the observed openings, coverage needs and any written service terms.