The Philippine Legislature enacted the Revised Penal Code, replacing the Spanish Código Penal of 1870. This comprehensive criminal code systematized felonies, penalties, and criminal liability in the Philippines.

The Revised Penal Code officially took effect on January 1, 1932, after a one-year period for preparation and dissemination. This marked the formal transition from Spanish colonial criminal law to a modernized Philippine penal system.

The Supreme Court ruled that common crimes committed in furtherance of rebellion are absorbed and cannot be separately charged. This established the doctrine that rebellion is a single, indivisible crime.

Republic Act No. 4661 amended various provisions of the RPC to increase penalties for crimes including physical injuries, robbery, and theft. The amendment reflected legislative response to rising crime rates during the 1960s.

The Supreme Court clarified the requisites for mistake of fact as a defense, requiring that the mistake be reasonable and without fault or negligence on the part of the accused.

Presidential Decree No. 532 amended Articles 122 and 306 of the RPC, increasing penalties for piracy and highway robbery. The decree reflected Marcos-era concerns about lawlessness and banditry.

Republic Act No. 7659 reimposed the death penalty and amended numerous RPC provisions, reclassifying certain crimes as heinous and imposing capital punishment for their commission.

Republic Act No. 8353 reclassified rape from a crime against chastity to a crime against persons, amending Article 335 and transferring it to Articles 266-A to 266-D. This landmark law recognized rape as a violation of personal dignity.

The Supreme Court upheld the constitutionality of RA 7659 and affirmed the death penalty for Leo Echegaray, who was subsequently executed by lethal injection in 1999, the first execution after the reimposition.

Republic Act No. 9346 prohibited the imposition of the death penalty in the Philippines, reducing all death sentences to reclusion perpetua. This law reflected evolving human rights values and international pressure.

Republic Act No. 10951 adjusted the amounts of fines and values of property in the RPC to account for inflation and changing economic conditions. The law updated monetary thresholds for crimes like theft, estafa, and malicious mischief.

The Supreme Court en banc established uniform guidelines for awarding civil indemnity, moral damages, and exemplary damages in criminal cases, creating a comprehensive matrix based on the penalty imposed.

Republic Act No. 11648 amended Articles 266-A and related provisions by raising the age determining statutory rape from 12 to 16 years old, while providing a close-in-age exception to avoid criminalizing consensual teen relationships.