G.R. No. 3418
Facts The accused, Chu Ning Co., entered the adjoining apartment of Ang Man Min on the night of 6 July 1905, armed with a large knife, and stabbed the sleeping victim, causing death a few hours later. He admitted the killing, claiming it was motivated by jealousy over a woman he believed to be his wife and alleged that he had been hired to do the stabbing, though no proof was offered. The trial court found him guilty of murder, citing the qualifying circumstance of treachery (attack on a sleeping person) and alleged aggravating circumstances of pre‑meditation and nocturnity, and imposed life imprisonment (cadena perpetua).

Issue Whether the evidence establishes the aggravating circumstances of (1) pre‑meditation and (2) nocturnity, thereby justifying a conviction for murder with the corresponding penalties, or whether any mitigating factors warrant a different assessment.

Ruling The Supreme Court affirmed the conviction for murder on the basis of the qualifying circumstance of treachery. It held that:

The alleged pre‑meditation was not proved; there was insufficient evidence of reflective, persistent deliberation as required by Art. 403 of the Penal Code.
The nocturnity aggravating circumstance was likewise unsubstantiated; the accused did not demonstrate that he selected the night for the purpose of committing the crime.
Nevertheless, the treachery (attack on a sleeping victim) sufficed to qualify the homicide as murder.
The aggravating circumstance of entering another’s dwelling (treated as a separate house) was offset by the mitigating circumstance under § 9, Art. 9, paragraph 7 of the Penal Code.

Accordingly, the life‑imprisonment sentence imposed by the lower court was within the maximum penalty for murder and was affirmed, together with costs.