The Solicitors Regulation Authority has yet to be told which 22 law firms are named in a dossier on private investigators suspected of illegal practices – but vowed this week to ‘establish the position’.

The Serious and Organised Crime Agency (SOCA) has passed the list – which also features insurance and financial services companies – to the Commons Home Affairs Select Committee but insisted that it remain confidential. Deputy prime minister Nick Clegg last week joined calls for its publication.

An SRA spokesman would not confirm whether the regulator has asked for the dossier, but did confirm the authority has yet to be provided with any evidence. ‘If we receive any such evidence, we will assess it in the usual way and decide whether to investigate,’ he added.

Illegal hacking would be covered by principle 1 of the code of conduct to uphold the rule of law.

A spokesman for the Law Society said there is a ‘legitimate and proper role’ for private investigators in assisting the legal process.

‘Nevertheless, the obligations on solicitors are clear,’ the spokesman said. ‘They must not break the law or conspire to do so. In using the services of a private investigator they must also comply with data protection regulations both domestically and internationally.’

The Society will review whether new guidance is necessary, he said.