The Supreme Court on Friday summoned the Inspector General of Police Punjab and Advocate General for April 11 on another case of defective investigation made by the police. Fatima Bibi had filed an appeal seeking cancellation of bails, earlier granted by the Lahore High Court, of two accused Shamas Tabriaz and Muddasar Hussain involved in murder of her son and his cousin. She told the court that her relatives had killed her son along with his cousin.