In-vehicle surveillance


This section deals with the applications and support available intended for security officers and off-vehicle transit personnel, and for downstream analysis, action and prosecution. Applications and support to the driver for operational purposes (safe use of doors, reversing) are dealt with under Driver Aids, Passenger Surveillance).

In-vehicle surveillance is implemented as part of a broader package of security measures. It is primarily a deterrent measure, as it usually cannot prevent an incident from happening, but it greatly increases the chance of detection and prosecution.

In-vehicle surveillance is used to provide enhanced security and safety on-board public transport vehicles. The main usages of the in-vehicle surveillance are:

  • To assist the driver to detect incidents and improper behaviour within the vehicle, especially on the rear portion of articulated buses and upper deck of double-deck buses which are out of his/her immediate view
  • To record images for subsequent viewing, both for specific incidents and general review. Images would be reviewed in case of allegations or suspicion of:
    • Assault or threatening behaviour towards staff
    • Assault of threatening behaviour towards other passengers
    • Bullying, especially among schoolchildren
    • Vandalism
    • Violation of bus bye-laws and inappropriate behaviour
    • Accidents or falls within the bus
  • To record images for use in police investigations and court cases
    • To provide evidence in support of prosecutions
    • To provide defence evidence in case of false/spurious claims
    • To detect perpetrators or suspects, including passengers who are suspected of having committed an offence before or after alighting from the vehicle
  • To provide images that can be used for passenger counting

Technologies, data and resources

In-vehicle surveillance is invariably performed using CCTV. A number of cameras are located throughout the vehicle, either a small number (2-6) to cover the areas of highest risk/interest, or a larger number (c. 15) to give comprehensive coverage of the interior of the vehicles and the door areas.

Images are recorded by CCTV and stored on the vehicle, in the on-board computer or in a dedicated recording module. The memory usually has sufficient capacity for several days of recording. If the images have not been recovered or earmarked, then the data is overwritten as required.

Some systems will store images to hard memory in case of a trigger event, and they will not be erased until they have been recovered or manually cleared. Triggers include a special button pressed by the driver, any alarm button pressed by the driver, or detection of a substantial g-force (indicates collision or avoiding manoeuvre).

CCTV images are rarely transmitted, since the bandwidth requirements exceed available capacity. Instead, they are recovered manually when required. A few transport utilities have the capacity to transmit images in the event of emergency, but these are low-resolution still images to give the dispatcher and security personnel some idea of what is happening on the vehicle.

Storage and archive facilities are required for the images deemed worth keeping. Special procedures are required for images that might be used as evidence in Court.

Advantages and Cautions

The primary advantages of In-vehicle Surveillance are to:

  • Provide continuous and comprehensive monitoring of vehicle interiors
  • Allow events to be reviewed, to detect assaults, incidents, accidents and improper behaviour
  • Assist the transit authority/operator to improve security and sense of safety among passengers
  • Gather presentable evidence for prosecution of violations
  • Gather presentable evidence for defence against claims

The principal cautions in relation to In-vehicle surveillance are:

  • Image processing may not function well in conditions of low ambient light, or of low, bright sunlight into the vehicle (e.g. winter sun).
  • Continuity of evidence rules need to be understood, and compliant procedures established for capture, storage and handling of images and information. Failure to do so is likely to result in evidence being inadmissible in Court.
  • Costs of maintaining CCTV systems can be high
  • A good working relationships is required with the police and security personnel to establish effective response, and with the legal system to establish an effective legal deterrent

Relevant Case Studies