State of Punjab [AIR 1957 SC 623 1957 Indlaw SC 181] following Willie Slaney,this Court held: "In judging a question of prejudice,as of guilt,courts must act with a broad vision and look to the substance and not to technicalities,and their main concern should be to see whether the accused had a fair trial,whether he knew what he was being tried for,whether the main facts sought to be established against him were explained to him fairly and clearly and whether he was given a full and fair chance to defend himself