Acting Director-general of Health Andrew Bridgman says his right to make a final decision on the neurosurgery row is not related to legislation.
It arose from the South Island district health boards' specific request for arbitration on this matter, he said in an email response to questions from the Otago Daily Times regarding issues related to the legal situation.
"Arbitration by its nature is a process under which a final decision is sought to achieve resolution when the parties have been unable to reach a decision themselves.
"The primary feature of an arbitration process is that it is a binding process and that parties are expected to comply with the decision."
He was " fully aware" the decision might be contested.
"That's the case whenever a decision is made."
The most important point was that there was a highly qualified panel looking into how the South Island could most effectively organise its neurosurgical service to best serve the people of the South Island, he said.
Doubts have been raised about the ability of the Director-general to bind South Island district health boards to any decision he makes on the issue.
Furthermore, Southern District Health Board chief executive Brian Rousseau has said when the boards' chief executives referred the matter to the Director-general, the expectation was that non-binding arbitration would be involved.
In that circumstance the Director-general would conduct an independent evaluation, come to an independent conclusion and state the position he wished to be adopted.
Mr Rousseau's expectation was the Director-general would advise the boards' chief executives of his position and request the boards adopt it.
The chief executives could either agree with the position and recommend to their boards accordingly (which could then agree or disagree), or disagree with the position, leaving it up to the Director-general to "activate mechanisms so to direct the DHBs to adopt his recommendation if he so wished".
The Southern board has not passed any resolution seeking to give the Director-general the power to make a decision in this matter.
Questions put to Health Minister Tony Ryall were referred to the Ministry of Health, including one asking whether he had agreed to the boards delegating their power on this issue to the Director-general.
Other South Island boards have yet to respond to questions regarding their understanding of the referral process and whether they have passed any resolutions on the Director-general's power.