Miguel Ricart, 44, was given a 170-year sentence after he was found guilty of the murders of Desiree Hernandez Folch and Miriam Garcia Iborra, both 14 and Antonia Gomez Rodriguez, 15. The sentence was handed down under what is known as the Parot Doctrine, approved by the Spanish Supreme Court in 2008, allowing people convicted of terrorist killings and some other crimes to be imprisoned beyond the 30-year maximum previously set by Spanish law.
The court ruled the law cannot be applied retroactively, ThinkSpain reported Wednesday.
Ricart, who was 23 at the time of the killings, is scheduled for release in about 10 years, the report said. He could be freed considerably sooner because of good-time credits.
The girls, from the village of Alcasser in Valencia, were last seen in November 1992 hitchhiking to a disco.
When they were found buried in a single grave more than two months later, investigators determined they had been raped and tortured.
Antonio Angles, who was 26 in 1992, allegedly participated in the killings with Ricart, and investigators say he may have taken the lead role. He was spotted on a ferry from Lisbon to Ireland and jumped overboard as the boat approached the Irish coast.
His body has never been found, and he remains on Interpol's most wanted list.
The surviving parents of the victims say the ECHR decision is "the last thing they need."
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