MPs have told the Serious Organised Crime Agency (Soca) that the names of about 100 businesses, including the law practices, must be published by Monday, 9 September. If Soca does not comply then the MPs - those on the Home Affairs Select Committee - will themselves publish the list, according to The Times.

So far investigations in the UK have focused on highlighting how parts of the British media broke the law in hacking into the mobile phones of celebrities or victims of crime. In many cases, the journalists worked with private investigators. But it has emerged that the investigating body, Soca, has details of non-media businesses - including the law firms - which also used the investigators. 

The inclusion of a law firm's name on the list does not mean, however, that it has done anything illegal. It signifies that it was listed as a contact of the investigator - and this relationship may have been entirely above board. However, firms may want to spell out exactly what the relationship was, rather then being subject to speculation.