Principal District Judge Alamelu Natarajan sentenced the trio to undergo double life imprisonment for the brutal murder and 10 years RI for the theft of offerings in the 'hundi' and ornaments adorned by the presiding deity of Lord Velayudhasamy Temple near Vellakoil on July 4.
All sentences would run concurrently, the Judge said imposing a fine of Rs 40,000 on the three.
According to the prosecution, when watchman Mahali tried to resist and prevent the three men from stealing, they murdered him with sharp-edged weapons.