People v. Yatar

On June 30, 1998, seventeen-year-old Kathylyn Uba was left alone in her grandmother's house in Rizal, Kalinga. Witnesses saw appellant Joel Yatar, the husband of her aunt, at the back of the house that morning, and at 12:30 p.m. saw him descend the ladder from the second floor and run to the back of the house. He was later seen in a different shirt. That evening her grandmother found Kathylyn's naked body on the second floor with multiple stab wounds and her intestines protruding. A bloodied white shirt was found near the house. Semen was found in the victim's vaginal canal, and DNA testing by the U.P. National Science Research Institute found appellant's DNA profile identical to that of the semen. Two days after being taken into custody, appellant ran from the police station while going to the toilet and was recaptured. The RTC convicted him of rape with homicide and imposed death. On automatic review, he challenged the witnesses' credibility and argued that the blood sampling and DNA tests violated his right against self-incrimination and were an ex post facto law.

1. 1Whether the DNA evidence was admissible and reliable.
2. 2Whether taking appellant's blood sample for DNA testing violated his right against self-incrimination, or the use of DNA testing was an ex post facto law.
3. 3Whether the evidence proved his guilt beyond reasonable doubt.

The conviction was affirmed with modified damages. The Court described DNA as the same in every cell and unique to each individual except identical twins, and a source of both inculpatory and exculpatory evidence. Citing People v. Vallejo, it held that courts assessing DNA evidence should consider "how the samples were collected, how they were handled, the possibility of contamination of the samples, the procedure followed in analyzing the samples, whether the proper standards and procedures were followed in conducting the tests, and the qualification of the analyst." Dr. de Ungria was qualified as an expert, and the gene types from appellant's blood matched the semen. Applying Daubert v. Merrell Dow, the PCR-STR evidence was relevant and reliable because it was based on scientifically valid principles. The right against self-incrimination is "not against all compulsion, but against testimonial compulsion." A person "may be compelled to submit to fingerprinting, photographing, paraffin, blood and DNA," and appellant in any case gave his blood sample in open court with counsel. There was no ex post facto issue, because DNA profiling concerns the admissibility and weight of evidence. The DNA match, the bloodied shirt and the thirteen circumstances found by the trial court, including his flight, formed an unbroken chain. His alibi failed because he lived about 100 meters from the scene. The death penalty was affirmed, three Justices noting their reservation on the constitutionality of R.A. 7659. Civil indemnity was set at P100,000, actual damages at P93,190 and moral damages at P75,000, and exemplary damages were deleted.