THE controversial academic commissioned to carry out the flawed study on the return of third-level fees for the Department of Education is the husband of education minister Batt O'Keeffe's personal assistant.

The Sunday Tribune has established that Dr Noel Woods' wife Katherine was first appointed as the then junior minister's personal assistant in August 2004.

She had also run his constituency office prior to that, sources said, and has stayed working with him since he became the minister for education. Dr Woods, who is a dental economist, estimated in a study "commissioned" by Minister O'Keeffe that the return of third-level fees could yield €530m to the exchequer.

However, it subsequently emerged that he had made a gross miscalculation and he was forced to revise the figures downwards to just €130m.

The Department of Education said no fee had been paid to Dr Woods and that the study was done as a personal favour for the minister.

But the unusual request backfired on Batt O'Keeffe when the enormous discrepancy in the figures was uncovered last week.

The two men have been close personal friends for nearly 20 years, both living close to each other in the minister's base in Ballincollig, Co Cork.

A departmental source said: "The report was given to the minister. This wasn't a formally commissioned report and no money was exchanged.

"He miscalculated and got them wrong. The minister does know him and he is a friend of his.

"He has not been appointed as an adviser to the minister. It's just a favour he did for him but instead of giving us a one-year figure, he gave us a four-year figure."

Dr Woods does not work in the Department of Economics at UCC having moved to the Centre for Policy Studies in the college. His area of expertise is in 'dental economics' and he was awarded a €300,000 grant last year by the Health Research Board to investigate remuneration in the "treatment provision of oral health".

Minister O'Keeffe said: "Obviously, it's embarrassing. There is no point in saying otherwise… when I read the figures, I thought they were high. But I didn't question the accuracy at the time … [it is] just one of those things, it happens and we move on from it."

The Higher Education Authority and a tax expert are also now preparing realistic projections for the Department of Education, O'Keeffe said.

Dr Woods' original analysis had stated revenue of between €220m and €530m was possible if fees for third-level students were brought back. However, the figures were subsequently downgraded to between €55m and €135m.

The projected revenue appeared faulty from the beginning as a similar estimate by the former education minister Noel Dempsey had stated that €15m was the most that could be earned by the reintroduction. Dr Woods said the mistake came about because he had overestimated the number of students entering college in each year.