Judge V G Anilkumar of District and Sessions Court in Thalassery rejected the plea of Jayarajan, who had been summoned by CBI in connection with the probe, holding that the petitioner cannot be granted the relief since he was not an accused in the case.
CBI counsel S Krishnakumar opposed the bail plea on the ground that the accused in the case had also been booked under the Unlawful Activities Prevention Act.
In his petition, Jayarajan contended that the summons were "politically motivated" and the move was only to arrest and harass him.
42-year-old Manoj, a district functionary of RSS, was hacked to death in the politically-volatile Kathiroor in Kannur district on September 1, 2014 allegedly by a group of CPI-M workers.
CBI, which took over the investigation in the case, had filed a charge sheet against 19 accused in the Thalassery court in March last year.