IMAGES should be only captured on CCTV in taxis where it is "clearly justifiable" and audio recordings should only be made on "very rare" occasions, according to advice from the Information Commissioner.

In 2012, Southampton City Council was ruled to have breached data protection rules by introducing a requirement that all taxis install CCTV equipment to constantly record both drivers and passengers.

In Scotland, council policies vary, but they can set down conditions that audio recording can only be carried out using a "panic button" operated by the driver.

Emma Carr of privacy group Big Brother Watch said passengers should be told when they are being recorded.

She added: "CCTV is not the silver bullet that it is often sold as being and other factors that may increase the risk to both drivers and passengers should not be ignored the moment that recording equipment is installed."