The involvement of the bar in the formulation of new attorney advertising restrictions marked an unprecedented collaboration between the legal community and court administrators, and one entered into with considerable consternation, a top judge revealed Thursday.

Eugene F. Pigott Jr., now a judge of the New York Court of Appeals, said the presiding justices were reluctant to solicit opinions from the bar in drafting a new disciplinary rule on advertising, largely because they had never done so before. But ultimately the judges “knew what we didn’t know” and began a cooperative venture, he said.