A women rights' party-list lawmaker cautioned on Sunday the Department of Justice (DoJ) against hastily using a principal suspect in the controversial murder of a beauty queen's sister, as a state witness.

Gabriela Party-list Rep. Liza Maza said that the DoJ should first examine closely the testimony of Manuel Montero, alleged suspect in the killing of Ruby Rose Barrameda-Jimenez, before deciding to take him as a state witness.

She said the gravity of Montero's participation in the murder should never be taken for granted by the DoJ.

“Montero should be indicted for his participation in the killing of Ruby Rose. He admitted he is one of those who killed Ruby Rose,” Maza of Gabriela said.

Ruby Rose was the sister of beauty queen Rochelle Barrameda. She had been missing before her supposed remains — packed a drum filled with cement — were recovered in Manila Bay.

“The DoJ should study very well the case before making Montero a witness, like looking carefully his credibility as a state witness," she added.

While they want justice for Ruby Rose, Maza warned that disreputable witnesses might just result in a failed case.

"Marami na rin kasi na naging state witness but it turned out na questionable ang personality. May iba pa bigla na lang mag retract so naiiba ang kwento,” she said, noting that “in Ruby Rose case, Montero doesn’t only saw the alleged killing incident but he is also a perpetrator.”

Montero, who worked as operations manager of the family-owned Buena Suerte Jimenez Fishing and Trading Co. (BSJ) for over 13 years from 1994, had admitted to a murder of Ruby Rose which resulted to the recovery of a drum containing Ruby Rose's supposed cadaver.

But records showed that he was fired from his job in 2007 by Lope Jimenez for “various infractions” including stealing from the company.

Maza said that if Montero's claims prove to be credible then he should be entitled to be a state witness.

“We in the Gabriela condemned the killing of Ruby Rose. She is one of the hundreds of women in the country who are being abused and exploited,” the party-list solon said.

Maza’s statement came after Dr. Raquel Fortun, professor of forensic pathology in the University of the Philippines, submitted a report to the DoJ where she explained that the dead woman that was recovered by the police at the bottom of the Manila Bay last June 10 was “very hard to identify.”

Fortun’s report also questions the method by which the police identified the body as that of Ruby Rose.

“The body found was already in an advanced stage of decomposition. You cannot use identification of relatives and clothes of the body in this case,” said Fortun.

Fortun went to the crime laboratory of the Philippine National Police last July 21 to examine the pieces of evidence gathered by police in the Ruby Rose murder case upon approval of the investigating DoJ panel.

During inspection, it was found out that the police have yet to conduct actual testing of DNA samples from the dead body.

She added that the samples taken from the woman — specifically from her muscles and posterior — could also not be used to get conclusive DNA test results.

Fortun, who pioneered forensic pathology in the country, said the samples should have been taken from the bones since the body was already decomposing.