Manila: The Supreme Court acquitted a senator's son and six other scions of rich families of the murder of an 18-year-old girl, her mother and a younger sister in 1991.

Seven Supreme Court judges reversed the findings of two lower courts that Hubert Webb, the son of former Senator Freddie Webb, and his six companions, were guilty of raping and killing of Carmela Vizconde, then 18, in her family home in Parañaque on June 30, 1991. Also killed during the incident were her mother, Estrellita, 47, and sister, Jennifer, 7, said Supreme Court spokesman Jose Midas Marquez.

The prosecution failed to establish beyond reasonable doubt that Webb and his companions were guilty. Former policeman Gerardo Biong, who allegedly destroyed evidence after the incident at the house of the Vizconde, had also been implicated.

"They are ordered to be released from detention," said Marquez, adding that Supreme Court pointed to inconsistencies in the evidence of the prosecution, particularly the testimony of principal witness Jessica Alfaro.

The Supreme Court admitted Webb's testimony that he was in the United States when the massacre happened. Four Supreme Court judges, including Chief Justice Renato Corona, voted against the ruling. Four others abstained.

Nine people were accused of the crime. Two others, Artemio Ventura and Joey Filart, are still at large. Former Judge Amelita Tolentino of the lower court in Paranaque issued the guilty verdict on Webb and his companions in January 2000. The Court of Appeals upheld the conviction of the six in December 2005.