The Supreme Court on Thursday virtually deprecated the Punjab government's campaign for mercy to Balwant Singh Rajoana saying he was convicted in a case of broad daylight killing of a Chief Minister.

"There is a person convicted of the charge of killing. It was a broad daylight killing of a Chief Minister. Instances are replete where persons found guilty of the terrorist offences have got political support. There are leaders who have garnered support and come to power. How can they leave them?" a bench comprising Justices G S Singhvi and S J Mukhopadhyay said.

The bench expressed concern over the violent incidents that took place in Punjab during a bandh called by Sikh outfits to protest the hanging of Rajoana convicted in the killing of former Punjab Chief Minister Beant Singh on August 31, 1995.

"What happened in (last) four days is very telling. If the decision was taken at an appropriate stage, then the exchequer could have been saved crores of Rupees. It is all drama," the bench said while hearing a petition filed by another death convict from Punjab Devender Pal Singh Bhullar pleading to commute his capital punishment.

Bhullar pleaded his capital punishment be commuted to life imprisonment as there has been an "inordinate" delay in deciding his mercy plea and he is not mentally sound.

He had submitted that prolonged incarceration awaiting his execution amounted to cruelty and violated his fundamental right to life under Article 21 of the Constitution.

Bhullar was deported from Germany in 1995 after his application for political asylum was rejected in that country.