"If that happens, I will be doubly happy," he said.
Karunanidhi said the DMK party has been demanding abolition of death sentence for a long time.
The Supreme Court Tuesday commuted the death sentences of the three assassins of Rajiv Gandhi to life imprisonment. It held that the 11-year long delay in deciding their mercy petitions had a dehumanising effect on them.
The court said that life imprisonment would mean life in jail till end.
Gandhi was killed in May 1991. His assassins were convicted by a TADA court in January 1998 and were awarded death sentence, which was confirmed by the apex court May 11, 1999.
The three assassins - V. Sriharan alias Murugan, Arivu and T. Suthendraraja alias Santhan - sought their death sentence be commutted to life imprisonment on account of the inordinate delay of nearly 11-years in deciding their mercy petitions.