In any case in which an affidavit has been filed by the defendant, or a statement that he has a bona fide defense has been made to the court by his attorney, and the plaintiff recovers judgment, if the court is of the opinion that such affidavit was filed or statement made without just cause or for the purpose of delay, it may allow to the plaintiff, at its discretion, double costs, together with a reasonable counsel fee to be taxed by the court.