Queen's University Belfast, has been asked by a senior graduate to come clean over the high cost of compensation pay-outs.
Alex Attwood, vice chairman of the university's graduate association, said he believed the total cost of discrimination cases at Queen's to date was about Pounds 500,000.
And Queen's senate was told last week that 24 complaints against the university have yet to be dealt with by the Fair Employment Commission.
The developments came as new statistics showed the recruitment of staff to Queen's in the last year was broadly in line with the make-up of the "economically active" population.
Mr Attwood, who is also a member of Queen's convocation, said: "It is to be welcomed that a greater balance is being achieved between the respective communities employed at Queen's.
"However, the university should now account for how much has been spent on legal and compensation costs arising from employment complaints which I now understand to be approaching Pounds 500,000.
"Queen's should also explain if anyone has been disciplined arising from cases alleging discrimination which have been settled."
The university recently revealed that Catholic recruitment has risen from 21 per cent in 1987, when the discrimination charges were first formally investigated, to 29 per cent.
Leslie Clarkson, chairman of the university's equal opportunities group, said: "We have shown a significant improvement in our policy and practice in fair employment and equal opportunities but we are perfectly aware that much more needs to be done."