Creating a database of the 11million adults who work with children could ruin the lives of innocent people, the privacy watchdog warns today.

Richard Thomas, who is stepping down after more than six years as Britain’s first Information Commissioner, says he has serious concerns about the system being launched in October for the Independent Safeguarding Authority.

The ISA computer will contain detailed files on all the adults who work with children, whether professionally or as volunteers.

But it will not only record criminal convictions, but also any so-called soft intelligence on individuals – which could include unfounded allegations, rumours or gossip passed to the police or social services.

An official working for the ISA will then decide whether or not someone is fit to work with children – without the person knowing what he or she is accused of.

Mr Thomas said the database would contain ‘allegations, some rumour, some speculation’.

He added: ‘If (officials) start making wrong decisions or allows the data to get into the wrong hands the scope for damage to be done both to individuals and the system as a whole is quite considerable.’

Mr Thomas said the combination of treating rumours as relevant and the power to ban an individual from a job had the capacity to damage an innocent person in their ‘career, financially and socially’.