"At no time did I have any discussion with the proposed Review Panel members about the level of remuneration offered for the position," he wrote.
"My discussions with each of the individuals focussed on the nature of the task required of the Review Panel."
Mr Brownlee said it was his judgement that a higher daily fee was justified because of the important nature of the panel's work, including the requirement that all proposed Orders in Council be reviewed with 72 hours.
He said he also took into account the daily fees paid to High Court judges and those paid to the Canterbury Earthquake Recovery Commission.
Asked if he was happy with the process, Mr Key today said the Government tried to make sure pay scales were "at the modest end" but special skills were needed in particular cases.
He said he clearly remembered Mr Brownlee telling Cabinet the rates were not high enough.
"The advice that he gave us was that those pay rates were required, that those specialist skills and because of the nature of the process in Christchurch, it was appropriate."
Mr Key said he accepted Mr Brownlee at his word.
As well as Sir John, the panel includes former National prime minister Dame Jenny Shipley, company director and consultant Anake Goodall and former Ministry of Agriculture and Forestry chief executive Murray Sherwin.
Sir John last month said he had not made any inquiries about the fee when he was asked to do the job.
He said the very short turnaround of the panel's work meant they had to drop everything else, and described the fee as "very reasonable".
- NZPA