The Crown Prosecution Service is mulling charging decisions following a police investigation into an allegation of fraud referred by HM Courts & Tribunals Service five years ago.

The Metropolitan Police would not confirm whether the allegation is in relation to an estimated £15m legal aid fraud, a figure reported by the Sun newspaper today. Three judges are among those being probed, the tabloid said. 

The police force said in a statement: 'The MPS Operation Falcon Complex Fraud Team are investigating an allegation of fraud referred to police by HM Courts & Tribunals Service in January 2013. Three people have been arrested and nine people interviewed under caution by police and a file has been referred to the Crown Prosecution Service for a charging decision.'

The Solicitors Regulation Authority would not confirm how many solicitors are among the 12 suspects. A spokesperson for the regulator said: 'We are aware of the issue, and have been working with the police on this. We await conclusion of any other proceedings before deciding on any action of our own.'

The judiciary has been approached for comment.