Madison — A judge's hold on Gov. Scott Walker's union bargaining bill should be kept in place, Dane County District Attorney Ismael Ozanne argued Tuesday. In a filing with a state appeals court, the Democratic district attorney argued that the law, which sharply curtails collective bargaining by public workers, is effectively void because a committee violated the state open meetings law in passing it.Without the allegedly improper committee vote, the later passage of the law by the Senate and Assembly "could not and would not have happened," Ozanne argued.