Roger Pearson looks at how a teacher's job prospects have been jeopardised by an old conviction that has come back to haunt him

A loophole in the Rehabilitation of Offenders Act 1974 has been exposed by a recent High Court action. It is one which undermines the spirit of the Act and could result in one-time offenders being penalised when applying for jobs or travel visas long after their past misdemeanours are officially considered "spent" convictions.

The case centres on a 29-year-old teacher who is in danger of losing the chance to work overseas because exposure of an old conviction could block his application for a visa.

As a teenager he was convicted of a minor theft. Under the 1974 Act that conviction is spent and should long be forgotten. However, confidential police records retain details of offences for 20 years. While those records cannot be made public, individuals are entitled to ask for a certificate giving details of computerised police records relating to them under the provisions of the 1984 Data Protection Act.

Employers and foreign governments have realised this and are increasingly asking job and visa applicants to produce the certificates which are obtained through the National Identification Service.

Employers have no right to make a direct request for a certificate but they can insist that, as a condition of employment, the employee obtains the information and hands it over.

The code of practice that the Association of Chief Officers operates contains a provision that "reportable offences" be retained for 20 years and ruled that this was not open to legal challenge.

There are provisions in the 1997 Police Act for the establishment of a system which would enable employers to obtain certificates of potential employees' previous convictions but would allow spent convictions to be dropped from these certificates.

However, according to leading civil liberties solicitor Louise Christian, of London firm Christian Fisher, that idea was dropped because of the cost.

Nevertheless, she says that the present system of "enforced third party access" to spent convictions is "disturbing and an abuse of the system".

Christian believes that because the courts are not in a position to do something about it, Parliament should.

"It is a very important civil liberties point and really the people who now need to be looking at it are the politicians," she said.

"It would be relatively straightforward to remedy. It could be cured by a simple amendment to the Data Protection Act providing that when these certificates are obtained from the police, spent convictions should not be included on them, if the request so specifies.

"A move such as that would not involve the spending of huge sums of money and would not involve the setting up of a new computer centre as envisaged under the Police Act provisions."