Top solicitor Alasdair Sutherland has called on the council to reveal the mystery legal advice given to officials about bus gates ahead of a planned court showdown.
A crowdfunding campaign, led by veteran retailer Normal Esslemont to fund a legal challenge against the controversial bus gates which have angered local businesses, has now passed £23,000.
And the lawyer tasked with undoing the council's city centre traffic measures has now, speaking exclusively to the Press and Journal, laid down the gauntlet to the local authority.
Mr Sutherland, a partner at Burness Paull, challenged the council to reveal the legal advice its officials were given about the implementation of the much-maligned bus gates.
The legal eagle, who successfully fought similar traffic measures in the Highlands, warned "everything will come out" in court.
He told the P&J: “There does seem to be a reluctance on the part of the administration and the officers to be completely candid about the legal advice they’ve received. If the council is very confident in its position, then they should not have any problems explaining the advice that they have received."
The Press and Journal has approached Aberdeen City Council for comment, and the full interview can be read on its website.