The court acquitted the police personnel on "benefit of doubts".
Kulwant Singh's father Tarlochan Singh (73), retired Principal of Khalsa School Kurali, was fighting to get justice for his son, who was allegedly killed in a fake encounter in 1989.
Tarlochan's only son, 20-year-old Kulwant who was fondly called Kid, was allegedly abducted by Punjab police personnel from a rented house at Mohali along with another person and later eliminated in a fake encounter near Sohana in 1989.
Tarlochan did not even get to see his son's body as the police had cremated him in a hurry. Kulwant is shown by police to be a Proclaimed Offender (PO) till now.
Kid, then a class tenth student of DAV school in Chandigarh was arrested in 1986 for having relations with a student political outfit which allegedly had extremist links.
He spent two years in jail and was released in 1988. He married in 1989 and was staying away from his family to avoid harassment of his parents at the hands of police.
The CBI had named seven Punjab police personnel in the case including Grewal, who was then the in-charge of Crime Investigation Agency (CIA) staff at Patiala, Nikka Ram, Gurcharan Singh, Chanan Singh, Dyal Singh, Amarjeet Singh and Birbal Das. One of the accused died during the trial.