Privacy rule change a boon for the unfaithful

A change in privacy rules for telephone numbers may prove a help for those conducting an affair. The Information Commissioner has decided phone numbers are personal data, and callers must have a means of wiping theirs from computer systems.

Dialling 1475 after a call will now remove the number from the 1471 system. When the person you called checks their phone, they will simply be told "we do not have the caller's number".

Although it has always been possible to prevent your number being recorded by dialling "141" first, there has been no way to yank it retrospectively from the network.

Philip Jones, the assistant data protection registrar, illustrated the need for the "wipeout" facility in his ruling to telecoms companies in February by asking what would happen if "a call is made to a residential number by someone who knows that the person he/she wants to call is likely to be alone". He said another member of the household could identify the number, and possibly the caller, by phoning 1471. Mr Jones said the personal data of the caller would have been given against his or her wishes.

The system has been operating since last month but has not been publicised.