NHS chiefs have put an official figure on losses due to fraud by Belfast solicitor George Brangam.
It has been revealed that a forensic accounting review concluded that £270,000 was skimmed from health trusts by the prominent lawyer.
Mr Brangam died in August, effectively halting a major PSNI Fraud Squad investigation.
He had specialised in legal work for NHS organisations over a number of years.
The Law Society, which regulates solicitors, closed his practice down in 2006 amid suspicions of major corruption.
Mr Brangam was alleged to have ripped off hospital trusts through double invoicing - billing them twice for the same work.
It is believed that the fraud probe also covered the possible fabrication of settlement figures in health service compensation proceedings.
The £270,000 losses estimate is cited in the Department of Health's recently-published accounts report for 2006/07.
It stated that the Department commissioned a team of forensic accountants to "assess the quantum of losses" for each of the health service organisations who had contacts with Mr Brangam's firm.
"The quantum of losses was calculated at £270,000," the report stated.
Solicitors have been tasked by the Department with recovering the £270,000 through civil proceedings.
This court action is aimed at recouping the money through the legal profession's insurance protection arrangements, the accounts document stated.
The details of the Brangam case are being examined by the watchdog Northern Ireland Audit Office.
Its report on the topic is expected to form the basis for a future investigation by the Assembly's Public Accounts Committee.
The issue of how the dishonesty was not detected at a much earlier stage is likely to be a major focus of this probe.
The Assembly's Health Committee may also wish to examine the subject.
Its chair, Iris Robinson, said earlier this year that lessons had to be learned from the case.
"There is clearly an onus on management within the health service and the broader public sector, as well as on public representatives, to ensure that these mistakes are not repeated," the DUP MLA argued.