Mr Pat Heneghan, the public relations consultant, is advising his friend the former Supreme Court judge Mr Hugh O'Flaherty "in a personal capacity".
Regarded as a troubleshooter with a particular expertise in crisis management, his clients include the businessman Larry Goodman, whose affairs were examined by the beef tribunal in the early 1990s.
Mr Heneghan also represents Bovale Developments, the building firm whose dealings are being investigated by the Flood tribunal. He also advised the Catholic Church as it attempted to deal with a spate of child abuse cases which were publicised in recent years.
In the 1980s, he advised the administrations of Dr Garret FitzGerald on communications matters. He is still regarded as a strong Fine Gael supporter. This contrasts with Mr O'Flaherty, who has links with Fianna Fail.
From Headford in Co Galway, Mr Heneghan (64) was a director of the tobacco firm P.J. Carroll before joining the PR group Bill O'Herlihy Communications in the early 1980s. He left in 1990 to form Pat Heneghan PR, and the company is now managed by his son Nigel.
It is thought that Mr O'Flaherty is not paying Mr Heneghan to work on his behalf. Mr Heneghan's work over the years would have brought him into contact with legal figures and both he and Mr O'Flaherty are members of Portmarnock Golf Club.