A former consultant from Birmingham-based Shakespeares is under investigation by West Midlands Police Fraud Squad on suspicion of theft.
John Vernon, who worked at the firm for over 30 years, has also had civil proceedings brought against him by Shakespeares after the firm identified a number of accounting irregularities within a limited number of clients accounts under Vernon's responsibility.
A judgment was obtained and a substantial interim payment order was made.
The order is believed to be in the sum of £350,000.
The former consultant, who specialised in property and trust work, was dismissed by Shakespeares in February last year. He also faces a hearing at the Solicitors Disciplinary Tribunal in early April.
However Andrew Argyle, managing partner at Shakespeares, says he believes Vernon has already surrendered his practising certificate.
A spokeswoman for West Midlands Police confirmed an investigation was underway over an allegation of theft of a substantial amount of money and that the matter had been referred to the police by Shakespeares and the Office for the Supervision of Solicitors (OSS).
He says that the matter was reported immediately to the Law Society through the OSS and an internal investigation was undertaken with assistance from PricewaterhouseCooper.
The police investigation is expected to continue through the year, and Argyle says when it is complete a file will go to the Crown Prosecution Service.