A brief history of DNA evidence in Philippine jurisprudence

Thirteen years after DNA first became “admissible and authoritative evidence in Philippine jurisprudence” via a Supreme Court en banc decision, the Senate Electoral Tribunal (SET) anticipates the submission very soon of DNA profiling results of presidential aspirant Senator Grace Poe.

 

On May 9, 2002, the high court admitted in evidence DNA samples from the bloodstained clothes of rape and murder victims in the case of  People v. Vallejo [G.R. No. 144656, 9 May 2002, 382 SCRA 192].

 

The SC said People v. Vallejo was the “first real breakthrough” and a step forward from March 8, 2001 when the justices “opened the possibility of admitting DNA as evidence of parentage, as enunciated in Tijing v. Court of Appeals [G.R. No. 125901, 8 March 2001, 354 SCRA 17].”

 

In 2001, the court knew that the University of the Philippines Natural Science Research Institute (UP-NSRI) DNA Analysis Laboratory had developed the capability to conduct DNA typing using short tandem repeat (STR) analysis. 

 

The learning curve of the SC on genetics was about to rise. They also knew enough in 2001 that DNA  analysis “is based on the fact that the DNA of a child/person has two (2) copies, one copy from the mother and the other from the father. The DNA from the mother, the alleged father and child are analyzed to establish parentage.”

 

People v. Vallejo was also a leap from 1997 in Pe Lim v. Court of Appeals (336 Phil. 741, 270 SCRA 1) when the high court's “faith in DNA testing, however, was not quite so steadfast”  and the magistrates  “cautioned against the use of DNA because DNA, being a relatively new science, (had) not as yet been accorded official recognition by our courts.”

 

In 1997, paternity cases still had to be resolved using “conventional evidence as the relevant incriminating acts, verbal and written, by the putative father.”

 

Then on October 2, 2007 the Supreme Court approved its “Rule on DNA Evidence” which defined terms, set procedures for the conduct of DNA testing, and established guidelines on how DNA evidence  shall be preserved, assessed for probative value, and applied to cases.

 

The court has in fact become quite familiar with even the different ways DNA testing is done:

 

“There are five (5) techniques to conduct DNA typing. They are: the RFLP (restriction fragment length polymorphism); reverse dot blot or HLA DQ a/Pm loci which was used in 287 cases that were admitted as evidence by 37 courts in the U.S. as of November 1994; DNA process; VNTR (variable number tandem repeats); and the most recent which is known as the PCR-([polymerase] chain reaction) based STR (short tandem repeats) method which, as of 1996, was availed of by most forensic laboratories in the world. PCR is the process of replicating or copying DNA in an evidence sample a million times through repeated cycling of a reaction involving the so-called DNA polymerize enzyme. STR, on the other hand, takes measurements in 13 separate places and can match two (2) samples with a reported theoretical error rate of less than one (1) in a trillion.” 

 

All of that in just the decade of 1997-2007.

 

Flash forward to September 2015.

 

Through counsel before the SC, and then in person before news media at the Senate on Monday, Senator Poe said she underwent DNA testing and expected the results of her DNA profile to be released soon. 

 

"We have rules in court that a DNA match is a conclusive presumption affiliation. So that [DNA test] would solve our problems here because you cannot argue with that anymore," said Justice Antonio Carpio, chairman of the SET, to Poe's counsel.

 

Later in the day, Poe said: “Nasa proseso na (ang DNA test). Sila ang lumapit sa akin.”

 

The DNA samples from the probable relatives were not from parents.

 

“(S)iempre hihintayin natin (ang DNA result) dahil hindi mismo sa mga magulang kundi sa mga siblings o mga kapatid (nakuha),” she said. 

 

“Basta ‘yung lumapit sa akin hindi ko relative ngayon. ‘Yung lumapit mukhang may basehan, yung lumapit nagpakita ng litrato," Poe added.

 

The 1987 Constitution requires that candidates for President, Vice President and Senator must be natural-born citizens. — with Amita Legaspi/Earl Victor Rosero/DVM, GMA News