Yet another indictment of politicians and bureaucrats in the continuing probe of collusion in the construction sector, and the resulting explosion in infrastructure construction costs in Montreal.

On Thursday, the Charbonneau Commission hearings heard from Serge Pourreaux, former Montreal supplies department director, who suggested that politicians at City Hall and senior bureaucrats in Quebec City seemed to wash their hands of seemingly well-documented infrastructure cost overruns in Montreal.

Pourreaux, who says he was forced into retirement, says former mayor Gerald Tremblay knew of the inflated costs, and was eager to see changes implemented to regain control over infrastructure contract tenders.

But he says he believes former executive committee chair Frank Zampino actively blocked attempts to address the issues, and he added, senior municipal affairs officials in Quebec City had to have known something was wrong, but that their attitude was that it was Montreal's problem, not theirs.