G.R. No. 103974 - People vs. Catanyag y Sta. Ana

The case involves the People of the Philippines as the plaintiff-appellee and Ariel Catanyag y Sta. Ana as the accused-appellant.
The accused was married to Elizabeth Catanyag y Calderon, a legally contracted marriage solemnized on August 18, 1983, in Cainta, Rizal. By 1988, the couple had separated.

On December 9, 1988, at approximately 4:00 p.m., Ariel Catanyag entered the residence of Girlie Nery, sister of Elizabeth, at No. 15 M. Borja Street in Taytay, Rizal, without permission.
The accused, seeking his estranged wife Elizabeth—who was out with her mother—began searching for her through the sala and dining room.
Elizabeth, upon noticing the accused, avoided him by turning to ascend or descend the stairs; however, he pursued her.
A conversation ensued wherein it was revealed that Elizabeth had no interest in reconciling with him, leading to a heated quarrel.

As Elizabeth attempted to evade him by hiding in the comfort room, the accused followed her.
Girlie, who was at the scene and preparing her wedding gown, overheard their quarrel and pursued the pair when she heard Elizabeth’s distress calls from behind a slightly ajar door.
Upon pushing the door, Girlie witnessed the accused stabbing Elizabeth with a Batangas knife, "vente nueve" (29).
In an effort to intervene, Girlie physically restrained the accused by boxing him at the back and pulling him away from the door.
Despite Girlie’s efforts, the accused continued his assault, even directing the blood-stained knife toward Girlie and subsequently stabbing Elizabeth again as she tried to protect her sister.
After the violent altercation, the accused fled the premises while Dante, Girlie's brother, and other family members attempted to provide aid, leading eventually to Elizabeth being rushed to Angono District Hospital where she later succumbed to severe hemorrhage.

The defense claimed that the accused suffered from insanity at the time of the killing, based primarily on the testimony of Dr. Edgardo Canlas.
Dr. Canlas, who conducted psychiatric and psychological examinations at the National Center for Mental Health in Mandaluyong, reported that the accused exhibited features of an "organic mental syndrome" marked by irritability, poor impulse control, poor judgment, and abnormal EEG findings.
Despite his findings, Dr. Canlas noted that the accused’s intelligence remained within the average level and that his physical and neurological examinations were largely normal.
Crucially, the examinations performed in 1990 were used to infer the accused’s mental state at the time of the crime in 1988, leading to controversy regarding the temporal validity of the findings.

On September 20, 1991, the Regional Trial Court of Antipolo, Rizal (Branch 71) rendered a judgment finding Ariel Catanyag guilty beyond reasonable doubt of parricide under Article 246 of the Revised Penal Code.
The Court sentenced him to reclusion perpetua, ordered him to indemnify the heirs of his deceased wife (except himself) in the amount of P50,000.00, and to pay the costs of the proceedings.

Whether the evidence sufficiently established that the accused was completely deprived of reason at the time he committed the crime.

The defense’s reliance on the psychiatric evaluation conducted in 1990 raised the question of its applicability to the accused’s mental state in 1988.
The issue centers on whether an "organic mental syndrome," characterized by certain abnormal behaviors, qualifies as a total lack of reason or freedom of will necessary to invoke the insanity defense.

Whether the burden of proving insanity as an exempting circumstance has been met by the accused.

The legal burden lies on the accused to demonstrate that he was insane such that his faculties of intelligence and judgment were entirely impaired during the commission of the crime.
The adequacy and timing of Dr. Canlas’ examinations and his admission that the organic mental syndrome could be transient or permanent further complicate this issue.

The applicability of jurisprudential standards on insanity as derived from both local and Spanish jurisprudence.

Previous decisions (e.g., People vs. Rafanan, People vs. Formigones) establish that mere abnormality of mental faculties is insufficient; there must be a complete deprivation of intelligence or will.
Whether those precedents lead to a strict interpretation that negates the possibility of considering partial mental abnormalities as an exempting circumstance.