The working party of five city councillors, including Cr East, was formed to negotiate with the appellants before the hearing.
The Star learned Cr East made a submission on the policy in 2013 when it was being drafted and asked the city council whether it was concerned it could be used by the appellants due to a perceived conflict of interest or predetermination.
City council's head of strategic policy Helen Beaumont told The Star it was satisfied the submission did not raise "any particular concerns".
"There is nothing to suggest that Cr East has not maintained an open mind in being a part of the council's working party," she said.
Cr East told The Star he resigned from the working party on Monday "in part" because of The Star's queries.
He said he had forgotten he had made a submission but as a precautionary measure he chose to resign.
"It is a course of action I would have taken in any situation. If there was a potential conflict it is better to be out of it and not have a reason for judicial review or whatever," he said.
In his 2013 submission he said licences should be issued on the merit of the application and closing times "at the discretion" of the licensing authority.
He wrote that bars that close at 1am would impact the financial viability of some and that the LAP was restrictive on trade and did not address the "real issues of pre-loading" with alcohol.