Just who was in charge of product safety within the Blood Transfusion Service Board in the years between Dr Jack O'Riordan's retirement as national director in December 1985 and Dr Terry Walsh becoming chief medical consultant in January 1987?
Whoever it was, it can hardly be said to be Dr Vincent Barry on the basis of his evidence over the past two days.
While he may have borne the title of chief medical consultant in the period in question, it is clear he played a minimal role, which diminished over time, in clinical and medical matters at Pelican House.
More importantly, he seems to have had little or no role in the selection and treatment of blood products for haemophiliacs, a responsibility which, he said, rested with a Dublin "team", comprising, among others, senior consultants, Dr Walsh and Dr James Wilkinson, and the chief technical officer, Mr Sean Hanratty.
The tribunal also heard yesterday that Dr Wilkinson, who is now deceased, took sudden and early retirement from the board on March 31st 1986. Dr Barry said he did not know why this decision was taken but "one had ideas". The issue will be explored further today.
Dr Barry described his role as a "caretaker" one and this seems to be borne out by documents from the BTSB - or rather the lack of them.
No additional remuneration was paid to the Cork-based consultant when he took up the post, which was combined with his role as regional director of the BTSB's Cork centre.
Nor was his appointment noted in the minutes of a board meeting, although he was referred to in documents by his new title.
Adding to the confusion was an informal arrangement between Dr Barry and Mr Noel Fox, the then chairman of the board, that Dr Barry could return to Cork and pass his Dublin-based duties over to Dr Walsh.
Dr Barry said the arrangement was agreed in June or July 1986, just a few months after he accepted the post. However, it was only noted by the board in October 1986.
The suggestion that Dr Walsh had assumed responsibility from mid-1986 seems to be borne out by documentation showing him, rather than Dr Barry, making a key decision to issue only heattreated Factor 9 and recall all untreated product in June 1986. Moreover, it appeared Dr Walsh was the person haemophilia treaters believed was in charge as letters on safety were addressed to him rather than Dr Barry.
Dr Walsh, who will be the next witness, is expected to contest the suggestion that he had overall responsibility for product safety during the period in question.
His counsel, Mr Charles Meenan SC, has indicated that Dr Walsh will argue the ad hoc management structure, combined with staff shortages, put him in an impossible situation.
It was interesting to note yesterday that Mr Meenan objected to Dr Barry being described as "acting chief medical consultant", a title which Mr Meenan pointed out appeared nowhere in the documentation.
It is expected the tribunal will also hear more in the coming days about the power struggles which developed within the BTSB after Dr O'Riordan's departure.
Dr Barry described yesterday how Dr Walsh and Dr Wilkinson were "hurt" by his appointment in 1986 and would pass him without speaking on the corridors of Pelican House.
Evidence of tension with Mr Hanratty was also apparent from a memo showing the technical officer put Dr Barry's name forward for a post which he did not want.
Dr Barry agreed the nomination was "disrespectful" and "an extraordinary insult" to him.