FACTS:

The petitioner, Domingo Naag, Jr., Marlon U. Rivera, and Benjamin N. Rivera, were charged with the crime of Frustrated Homicide for allegedly attacking and assaulting Joseph Cea with iron pipes, causing him to sustain fatal injuries. The incident occurred on November 21, 2008, in Magarao, Camarines Sur. The petitioners pleaded not guilty and claimed self-defense during the pre-trial.

The defense's version of the events was that the petitioners, who were employees of Metro Naga Water District (MNWD), were conducting emergency water flushing operations when they were suddenly attacked by Joseph and several others. Domingo recognized Joseph as someone he knew personally, and Marlon was struck on the head, causing him to become unconscious. Domingo fought back, and Benjamin joined in the altercation. The police arrived and brought the petitioners to the police station after receiving medical treatment.

On the other hand, the prosecution presented a different version of the events. Joseph claimed that he and his friends left a birthday party around 12:30 a.m. and encountered the petitioners. An argument ensued, and Marlon punched Joseph, causing him to fall to the ground. Joseph managed to escape with his friends and took shelter in a nipa hut. The petitioners pursued Joseph and severely assaulted him, causing him to lose consciousness. Joseph was then taken to the hospital.

After trial, the RTC found the petitioners guilty of Frustrated Homicide. The CA affirmed the decision, stating that there was insufficient evidence to prove that the petitioners acted in self-defense. The petitioners appealed the decision to the Supreme Court, arguing that their acts were justified under the circumstances and that the elements of intent to kill and conspiracy were not established.

The sole issue for the Court's resolution is whether or not the CA correctly upheld the petitioners' conviction for Frustrated Homicide.

ISSUES:

RULING:

PRINCIPLES:

• In a criminal case, the burden of proof lies with the prosecution to establish the guilt of the accused beyond reasonable doubt.

• Self-defense is a justifying circumstance that exempts the accused from criminal liability if the requisites provided by law are present -- unlawful aggression, reasonable necessity of the means used to prevent or repel it, and lack of sufficient provocation on the part of the person defending himself.

• In determining self-defense, the existence of unlawful aggression must be proven and the person claiming self-defense must show that he used reasonable means to repel the aggression.

• The credibility of witnesses and the assessment of their testimonies are matters best left to the discretion of the trial court, which is in the best position to observe their demeanor, conduct, and attitude during trial.