Senior civil servant Paul Priestly unsuccessfully appealed against his demotion from permanent secretary to deputy secretary, it has been revealed.
Mr Priestly was suspended as permanent secretary at the Department of Regional Development (DRD) last August after a series of controversies rocked the Government-owned Northern Ireland Water (NIW) company.
An independent review had led the then minister Conor Murphy to sack the NIW board chairman and three non-executive directors, but the episode was being probed by the Assembly's powerful Public Accounts Committee.
Mr Priestly was dramatically suspended from his role as the minister's top Government adviser.
This was after claims he helped draw up a letter for one of the review team which criticised the committee.
It has now emerged that Mr Priestly appealed the demotion and that the head of the Civil Service, Sir Bruce Robinson, said it was his decision to demote Mr Priestly.