Additional Sessions Judge Anju Bajaj Chandna awarded life terms to Mohd Kashim, Abdul Rehman, Saraft Ali and Sajid - all residents of Muzzafarpur in Uttar Pradesh, and imposed a fine of Rs 30,000 each on them.
The court observed the four were also involved in various cases of robbery and dacoity and therefore, cannot make any positive contribution to the society.
"It is clear that the convicts have committed heinous offences of robbery and murder only for the purpose of enriching themselves...The convicts cannot make any positive contribution to the society and deserve to remain behind bars for the rest of life," it said.
On March 11, 2007, the convicts had intercepted the car of Vinay Jain, a jeweller, while he was returning from work.
They shot him dead and looted the jewellery and valuables he was carrying in a bag.