NEW DELHI (AP) -- India's Supreme Court on Tuesday commuted the death sentences to life in prison for three men convicted of playing minor roles in the assassination of former Prime Minister Rajiv Gandhi.
The three have served more than 20 years on death row in Vellore Prison in southern Tamil Nadu state.
They denied knowing anything about the plot to kill Gandhi as he was campaigning in May 1991 for a return to the prime ministerial office. He was killed along with 17 others, including the female suicide assassin, as she greeted him with a garland of sandalwood beads and a bomb strapped to her chest during a rally in Tamil Nadu.
The attack -- orchestrated by Tamil Tiger rebels in neighboring Sri Lanka -- horrified the nation and virtually ended Indian support for the rebels in their decades-long fight for an ethnic Tamil homeland. All of the assassination's masterminds, who targeted Gandhi for sending Indian troops to Sri Lanka in 1987, were killed during or after the 1991 attack. Although the troops were sent to oversee a peace accord between the Tamil Tigers and the Sri Lankan government, they became embroiled in the war and fought the rebels for months.
The three men on death row were among 26 convicted of playing minor roles in the assassination plot. While they have been reviled across much of India, many ethnic Tamils in the south believe they were duped into taking part in a plot they knew little about.
Indian national Arivu Perarivalan was found guilty of buying a 9-volt battery used in the bomb, while Sri Lankans Murugan and Santhan -- who use only one name -- acknowledged they were Tamil Tiger rebels but said they were only pawns in a larger game they barely understood.
Mercy petitions they filed in 2000 were rejected in 2011.
Their lawyers argued that executing the three now, after they had already served long prison terms, would amount to an unconstitutional double punishment.
"This is a landmark judgment," said lawyer Yug Chaudhry, applauding the court for rejecting the idea that the prisoners should show proof of "the scars of mental suffering" in awaiting their executions for decades.
Human rights activists and lawyers also cheered the court's decision.
A "delay in disposing of mercy petitions of death row convicts amounts to degrading, inhumane treatment. It amounts to torture," rights lawyer Vrinda Grover said. "In this case also there has been substantial delay."
Hangings are rare in India, with four in the last 18 years, though there are some 400 prisoners on death row.
The Supreme Court last month agreed that "unexplained delay is grounds for commuting death penalty to life sentence" as it commuted 15 other death sentences.
Amnesty International said Tuesday's decision "shows the judiciary's willingness to uphold standards it set down for the treatment of prisoners on death row."
The Vellore Three, as they are known, were the only convicts left on death row in the case, after 23 others were released or had their sentences commuted to life. The last clemency granted was for Murugan's wife after Gandhi's widow, Sonia, asked in 1999 that no one be hanged. Sonia Gandhi is now leader of the governing Congress party and her son, Rahul, is seen as the party's prime ministerial candidate in parliamentary elections that must be held by May.
In a jailhouse interview in 2011 with The Associated Press, the three said they hoped for release someday.
"We feel it is only a matter of time before clemency is granted," said Santhan, who has embraced a Hindu spiritual life and hopes to study with Indian mystics in the Himalayas. Perarivalan said he dreamed of helping prisoners wrongly convicted.
On Tuesday, Perarivalan's mother -- who has visited her son weekly and brought him fresh fruit since he was imprisoned at age 19 -- said she was overwhelmed by the news.
"I now have peace of mind," Arputham Ammal, 67, told reporters in the Tamil Nadu capital of Chennai, according to the Press Trust of India news agency. "There should be more such judgments."
But the news was received bitterly in India's northernmost territory of Kashmir, where many are angry about last year's execution of Mohammed Afzal Guru for a 2001 attack on India's Parliament. A 2006 mercy petition was turned down by the president a few days before Guru -- a Kashmiri -- was secretly hanged in a New Delhi prison on Feb. 9, 2013.
The court's failure to act before Guru's execution tells people in the militarized region "that there is a separate law for Kashmir and the rest of the country," said Mehbooba Mufti, a prominent Kashmiri politician.
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