Adultery and Concubinage in the Philippines (RPC Arts. 333-334)

Generated: 2026-07-04 | Intellegal Deep Research

Answer Summary

Adultery (Article 333) and concubinage (Article 334) remain distinct crimes under the Revised Penal Code, both classified as private offenses that may be prosecuted only upon a sworn complaint filed personally by the offended spouse. Adultery punishes a married woman who has sexual intercourse with a man not her husband, and the man who knows her to be married; a single act consummates the crime. Concubinage punishes a married man only if he keeps a mistress in the conjugal dwelling, has sexual intercourse under scandalous circumstances, or cohabits with her elsewhere—mere isolated sexual intercourse does not suffice. The evidentiary burden and penalties are markedly unequal, a disparity that members of the Supreme Court have noted may violate the equal protection guarantee under the Constitution and international obligations such as CEDAW, though no majority ruling has struck down the provisions.

The governing statutes are Articles 333, 334, and 344 of the Revised Penal Code (Act No. 3815) and Rule 110, Section 5 of the Revised Rules of Criminal Procedure. The leading decision on the jurisdictional requirement that the complaint be filed personally by the offended spouse is Aurel Ann Chua-Chiba v. Jin Chiba and Michael Llona, G.R. No. 277020, 19 May 2025 (J. Leonen), which dismissed an adultery case because the complaint-affidavit was filed by the husband’s authorized representative rather than the husband himself. The Court held that the requirement is jurisdictional and rooted in Article 344. On concubinage, Emiliano Castro, Jr. v. Court of Appeals, G.R. No. L-22159, 31 July 1968, affirmed that cohabitation with a woman other than the wife, while the marriage subsists, constitutes concubinage. The disparity between the two crimes was discussed in concurring and dissenting opinions in G.R. No. 252739 (2024) and G.R. No. 244657 (2024), which acknowledged the unequal treatment but left the statutes intact.

The essential elements of adultery are: (1) the woman is legally married; (2) she has sexual intercourse with a man who is not her husband; (3) the man knows she is married. For concubinage, the elements are: (1) the man is legally married; (2) he commits any of three acts—keeping a mistress in the conjugal dwelling, having sexual intercourse under scandalous circumstances with a woman not his wife, or cohabiting with her in any other place; (3) the concubine knows the man is married. The penalties are: for adultery, prisión correccional in its medium and maximum periods (2 years, 4 months, 1 day to 6 years) for both offenders; for concubinage, prisión correccional in its minimum and medium periods (6 months, 1 day to 4 years, 2 months) for the husband, and destierro (banishment) for the concubine. The offended spouse must file the complaint against both guilty parties if both are alive; consent or pardon before filing bars prosecution.

The most common failure point is non-compliance with the personal complaint requirement. In Chua-Chiba, the case was dismissed because the complaint was filed by a representative, even though the husband’s own affidavit was attached. In United States v. Bacas, G.R. No. 5297, 19 October 1909, a complaint filed against only the wife was void. Another critical point is proof: for adultery, circumstantial evidence of cohabitation and intimate behavior may suffice (as in United States v. Feliciano, 36 Phil. 753 [1917]; Valencia v. People, G.R. No. 244657, 12 February 2024), but mere suspicion is not enough. For concubinage, the wife must prove not just sexual intercourse but one of the three specific modes, a much heavier burden.

Based on comprehensive database and web research, rulings from 2024-2026 confirm the continuing validity of both crimes. No legislative amendment has been enacted, though bills proposing a unified, gender-neutral crime of marital infidelity have been filed in Congress. The Supreme Court has not yet ruled on the constitutionality of the adultery-concubinage dichotomy in a dispositive majority opinion.

Section I — Issue Overview

1. What are the elements, penalties, and complaint requirements for the crime of adultery under the Revised Penal Code? This issue covers the statutory definition, the jurisdictional prerequisite of a complaint by the offended spouse, and the evidentiary standards that govern prosecution.

2. What are the elements, penalties, and complaint requirements for the crime of concubinage under the Revised Penal Code? This issue addresses the three distinct modes of committing concubinage, the lighter penalty structure, and the same complaint requirement, noting the historical anomaly that concubinage alone retained the private-crime character after Act No. 1773.

3. How do adultery and concubinage differ, and what is their present status under Philippine law, including constitutional challenges? This issue examines the gender-based disparity in elements and penalties, the jurisprudential acknowledgment of potential equal protection violations, and the legislative reform efforts.

Section II — Legal Analysis

Issue 1: Adultery — Elements, Penalties, and Who May File

Applicable Laws & Issuances

Article 333 of the Revised Penal Code defines adultery: a married woman who has sexual intercourse with a man not her husband, and the man who has carnal knowledge of her knowing her to be married, are both guilty of adultery. The penalty is prisión correccional in its medium and maximum periods (2 years, 4 months, 1 day to 6 years). If the offended spouse abandoned the offender without justification, the penalty next lower in degree is imposed. The crime is consummated upon a single act of sexual intercourse; every sexual intercourse constitutes a separate crime. (Adultery, A333 Revised Penal Code - Legal Resource PH; G.R. No. 244657 - Dissenting Opinion)

Article 344 of the Revised Penal Code and Rule 110, Section 5 of the Revised Rules of Criminal Procedure provide that adultery “shall not be prosecuted except upon a complaint filed by the offended spouse.” The complaint must include both guilty parties if alive, and cannot be instituted if the offended spouse has consented to the offense or pardoned the offenders. This requirement is jurisdictional: no court acquires jurisdiction to try the case without a valid complaint from the offended spouse. (AUREL ANN CHUA-CHIBA, petitioner, vs. JIN CHIBA and MICHAEL LLONA, respondents., G.R. No. 277020; MILAGROS DONIO-TEVES and MANUEL MORENO, petitioners, vs. HON. CIPRIANO VAMENTA, JR., as Presiding Judge, Branch III, Court of First Instance, Negros Oriental, PABLO E. CABAHUG, as City Fiscal of Dumaguete, and JULIAN L. TEVES, respondents, G.R. No. L-38308)

Case Law Analysis

Aurel Ann Chua-Chiba v. Jin Chiba and Michael Llona, G.R. No. 277020 — 19 May 2025 (J. Leonen)

Focus of Dispute: Whether a complaint-affidavit filed by the offended spouse’s authorized representative, with the spouse’s own affidavit merely attached, satisfies the jurisdictional requirement of Article 344.

Facts: Jin Chiba, through his representative Marvin Ayende, filed a complaint-affidavit for adultery against his wife Aurel Ann Chua-Chiba and Michael Llona. The MeTC dismissed the case for lack of jurisdiction because the complaint was not filed personally by the offended spouse. The RTC reversed, ruling there was substantial compliance. The Supreme Court granted Aurel’s petition.

Arguments:

• Petitioner (accused wife): The complaint was not filed by the offended spouse as required; the court never acquired jurisdiction.
• Respondent (husband): His own complaint-affidavit, attached to the representative’s filing, substantially complied with the law.

Disposition: Petition granted; RTC decision reversed; adultery case dismissed for lack of jurisdiction.

Ratio Decidendi: The Court held that the requirement in Article 344 and Rule 110, Section 5 that the complaint be filed by the offended spouse is jurisdictional.

“Adultery, being a private offense, cannot be prosecuted except upon a complaint filed by the offended spouse… [T]he requirement in Article 344 (that there shall be a complaint of the offended party) is jurisdictional… ‘it is the complaint that starts the prosecutory proceeding.’”

A complaint initiated by a representative, even with the spouse’s affidavit attached, does not satisfy the requirement because it is not the spouse who instituted the action.

Evidence Evaluated: The complaint-affidavit was filed by the representative; the husband’s affidavit was merely an annex. The MeTC had correctly ruled this insufficient.

Precedential Status: This 2025 ruling is the most recent and authoritative statement on the personal complaint requirement, reinforcing strict compliance.

United States v. Martina Bacas, G.R. No. 5297 — 19 October 1909

Focus of Dispute: Whether a criminal complaint for adultery filed against only the wife, without including the male paramour, is valid under Article 434(2) of the then-applicable Penal Code.

Facts: The husband filed a complaint for adultery only against his wife, Martina Bacas, and not against the unknown American she was found with.

Disposition: Case reversed and dismissed.

Ratio Decidendi: “Paragraph 2 of article 434 of the Penal Code provides that the injured husband can not enter a complaint for adultery except against both guilty parties… the complaint has only been entered against the adulteress, but not against the other guilty party.” The requirement is mandatory, and Act No. 1773 did not alter this condition.

Precedential Status: Still good law; Article 344 of the RPC continues the requirement that both guilty parties must be included.

Milagros Donio-Teves v. Hon. Cipriano Vamenta, Jr., G.R. No. L-38308 — 26 December 1984

Focus of Dispute: Whether an adultery prosecution remains valid after the offended husband dies during the pendency of the case.

Disposition: Petition dismissed; trial ordered to continue.

Ratio Decidendi: “Death of the offended party is not a ground for extinguishment of criminal liability… The participation of the offended party is essential not for the maintenance of the criminal action but solely for the initiation thereof.” Once a valid complaint is filed, the action proceeds even if the complainant dies.

Precedential Status: Established the rule that the offended spouse’s role is limited to initiation, not maintenance.

United States v. Margarita Feliciano, G.R. No. 12724 — 10 August 1917

Focus of Dispute: Whether circumstantial evidence can sustain an adultery conviction, and whether acquittal of one co-accused mandates acquittal of the other.

Ratio Decidendi: The Court held that strong circumstantial evidence of cohabitation, intimate acts, and living together as husband and wife suffices to prove adultery, as direct proof of sexual intercourse is often unavailable. Acquittal of one party does not automatically require acquittal of the other.

Precedential Status: Affirmed in Valencia v. People, G.R. No. 244657 (12 February 2024), where the Supreme Court reiterated that circumstantial evidence may establish adultery.

Recent Developments

The 2025 decision in Chua-Chiba reaffirmed the strict jurisdictional nature of the personal complaint requirement. No legislative amendments to Article 333 have been enacted. The Supreme Court has not issued a ruling on the constitutionality of the adultery provision, though concurring and dissenting opinions in G.R. No. 244657 and G.R. No. 252739 have questioned its gender-based disparity.

Analysis

Adultery under Article 333 requires proof of three elements: (1) the woman is legally married at the time of the sexual act; (2) she had sexual intercourse with a man who is not her husband; (3) the man knew she was married. Marriage may be proved by testimony of the spouses and witnesses—documentary evidence is not indispensable, as held in United States v. Cecilia Memoracion and Dalmacio Uri. The crime is committed upon each act of intercourse; it is an instantaneous crime, not a continuing one (Laureano Fernandez v. Judge Lantin). The penalty for both the married woman and her paramour is prisión correccional in its medium and maximum periods, i.e., 2 years, 4 months, 1 day to 6 years. If the offended spouse abandoned the offender without justification, the penalty is reduced to the next lower degree.

The offended spouse must file a sworn complaint personally. This requirement is jurisdictional and cannot be delegated, as the Court emphasized in Chua-Chiba. The complaint must be filed in court, not merely with the prosecutor’s office, and must name both guilty parties if alive. Pardon or consent before the complaint is filed bars prosecution; pardon after filing is ineffective (People v. Consolacion Infante). The offended spouse need not be alive throughout the trial—once a valid complaint is lodged, the action survives the complainant’s death (Donio-Teves; People v. Ilarde).

Evidentially, direct proof of sexual intercourse is not required. The Supreme Court has consistently held that circumstantial evidence—such as cohabitation, discovery of the accused together in compromising circumstances, or intimate correspondence—may establish guilt beyond reasonable doubt. In Valencia v. People (G.R. No. 244657, 2024), the Court affirmed a conviction based on testimony that the accused were seen naked together and living as a couple.

Issue 2: Concubinage — Elements, Penalties, and Who May File

Applicable Laws & Issuances

Article 334 of the Revised Penal Code defines concubinage as committed by any husband who: (a) keeps a mistress in the conjugal dwelling; (b) has sexual intercourse under scandalous circumstances with a woman who is not his wife; or (c) cohabits with her in any other place. The concubine must know the man is married. The penalty for the husband is prisión correccional in its minimum and medium periods (6 months, 1 day to 4 years, 2 months); the concubine suffers destierro (banishment). As with adultery, a complaint must be filed by the offended spouse against both guilty parties, and consent or pardon before filing bars prosecution. (Philippines: Information on adultery laws; Concubinage Under Article 334 RPC)

Historically, Act No. 1773 (1907) converted adultery and several other private crimes into public crimes prosecutable de oficio, but it “apparently overlooked” concubinage. Thus, under the old Penal Code, concubinage remained a private crime extinguishable by condonation, while adultery became a public crime. The Supreme Court resolved this anomaly in several cases, holding that concubinage retained its private nature. The Revised Penal Code (Act No. 3815, 1930) restored both adultery and concubinage as private crimes under Article 344. (Public Prosecution of the Crimes of Adulterio, Estupro, Rapto, Violacion, Calumnia, and Injuria, Abolishing the Right of Pardon by the Aggrieved Party in Such Cases, and Providing for a Special Civil Action for Damages Therein (Act No. 1773); THE PEOPLE OF THE PHILIPPINE ISLANDS vs. AGAPITO FRANCISCO and JOSEFINA MANTELO, G.R. No. 29531)

Case Law Analysis

Emiliano Castro, Jr. v. Court of Appeals, G.R. No. L-22159 — 31 July 1968

Focus of Dispute: Whether the accused husband’s cohabitation with another woman, while still legally married, constitutes concubinage.

Facts: Emiliano Castro Jr. married Flordeliza in 1952. They separated in 1954 but the marriage remained undissolved. From 1956 to 1959, Castro lived openly with Lolita Flojo at his former matrimonial home. Evidence included a birth certificate showing Flojo used his surname and bore his child, and SSS forms listing him as her husband. The wife filed a complaint for concubinage.

Disposition: Conviction affirmed. Indeterminate sentence of 3 months to 1 year imprisonment.

Ratio Decidendi: The Supreme Court found that cohabitation with a woman other than the wife while the marriage subsists constitutes concubinage under Article 334. The defense of condonation was rejected because the wife’s letters referring to Flojo as his “querida” and her separate legal separation suit demonstrated she had never forgiven the offense.

Precedential Status: Still cited for the definition of cohabitation as an element of concubinage.

People v. Pedro Pitoc, G.R. No. 18513 — 18 September 1922

Focus of Dispute: Whether living with a former mistress after marriage constitutes “cohabitation” under the amended concubinage statute.

Ratio Decidendi: The Court held that “cohabit” means “to dwell together as husband and wife for some period of time, as distinguished from occasional, transient interviews for unlawful intercourse.” The defendant’s admitted living with another woman as his wife satisfied the element.

Fernando Maulit v. Domingo Samonte, G.R. No. 34484 — 13 December 1930

Focus of Dispute: Whether concubinage, after Act No. 1773, could still be extinguished by pardon of the offended spouse.

Disposition: Habeas corpus granted; prisoner released.

Ratio Decidendi: The Court held that Act No. 1773 converted adultery into a public crime but overlooked concubinage, which remained a private offense extinguishable by the offended party’s condonation. This decision was based on the Penal Code then in effect; under the current RPC, both crimes are private and can be barred by pardon before filing, but not after.

Recent Developments

No recent Supreme Court rulings (2024-2026) squarely address the elements of concubinage in a contested criminal proceeding. Administrative cases involving court employees have considered extramarital affairs as “disgraceful and immoral conduct” but do not modify the criminal elements (PRECIOUSA CASTILLO-MACAPUSO vs. ATTY. NELSON B. CASTILLEJOS, JR. & ANONYMOUS vs. PRECIOUSA C. MACAPUSO). The concurring opinion in G.R. No. 252739 notes the legislative acknowledgment of the bias in these provisions.

Analysis

Concubinage under Article 334 requires: (1) the man is legally married; (2) he commits one of three acts—keeps a mistress in the conjugal dwelling, has sexual intercourse under scandalous circumstances, or cohabits with a woman other than his wife; (3) the concubine knows the man is married. Unlike adultery, one isolated act of sexual intercourse is not enough; the law demands either cohabitation (continuous living together as husband and wife), intercourse with scandalous publicity, or maintenance of a mistress in the family home. This makes the crime significantly harder to prove.

Cohabitation is defined as living together as husband and wife for some period, not merely occasional meetings (Pitoc). Proof may include documentary evidence such as birth certificates showing the woman using the husband’s surname, joint residence, and public representation as a couple (Castro). “Scandalous circumstances” requires that the sexual act be open and public, causing moral disturbance. “Keeping a mistress in the conjugal dwelling” means the woman is lodged in the house where the family resides.

The penalty for the husband is prisión correccional in its minimum and medium periods (6 months, 1 day to 4 years, 2 months). The concubine suffers destierro, which is banishment to a specified distance from the offended spouse’s residence, not imprisonment. Both are private crimes under Article 344; only the offended wife may file the complaint, and both guilty parties must be included. Pardon or consent before filing bars prosecution. The complaint requirement is equally jurisdictional.

The historical anomaly under Act No. 1773—where concubinage alone remained extinguishable by pardon after filing—was corrected with the RPC, which now treats both crimes uniformly as private offenses. The Supreme Court in In re Juan C. Isada confirmed that concubinage involves moral turpitude, which has professional disciplinary consequences for lawyers and public officials.

Issue 3: Differences Between Adultery and Concubinage, and Present Constitutional Status

Applicable Laws & Issuances

The disparity is embedded in the text of Articles 333 and 334 of the Revised Penal Code and the complaint mechanism of Article 344. No explicit statute mandates equal treatment. Republic Act No. 9262 (Anti-Violence Against Women and Their Children Act of 2004), while not amending the RPC, acknowledges in its legislative history the gender bias in these provisions. The 1987 Constitution guarantees equal protection (Article III, Section 1) and the State’s obligation to ensure fundamental equality before the law of men and women (Article II, Section 14). The Magna Carta of Women (R.A. No. 9710) and the UN Convention on the Elimination of All Forms of Discrimination Against Women (CEDAW) also inform the debate.

Case Law Analysis

The most significant jurisprudential discussion of the inequality is found in concurring and dissenting opinions, not in a majority ruling that struck down the provisions. In G.R. No. 252739, the concurring opinion of Justice Inting (16 April 2024) noted:

“They [lawmakers] particularly noted that the Revised Penal Code imposes heavier penalties on adultery than on concubinage. Moreover, in adultery, the married woman is immediately liable the moment that she has sexual intercourse with a man who is not her husband; on the other hand, for a married man to be liable for concubinage, other conditions are required, such as cohabitation and sex under scandalous circumstances.” (G.R. No. 252739 - Concurring Opinion)

The dissenting opinion of Justice Leonen in G.R. No. 244657 (12 February 2024) observed:

“Our law and jurisprudence on concubinage and adultery discriminates on the basis of sex because of the harsher penalty that is imposed on women… Concubinage is harder to prove but carries a lighter penalty.” (G.R. No. 244657 - Dissenting Opinion)

The concurring and dissenting opinion in A.M. No. MTJ-16-1886 (25 July 2017) expressed the view that the adultery and concubinage provisions “may violate the equal protection clause of the Constitution and ‘fundamental equality before the law of men and women.’” (A.M. No. MTJ-16-1886 - Concurring & Dissenting Opinion)

However, the Supreme Court has not yet issued a final, binding decision declaring either Article 333 or 334 unconstitutional. In Tenchavez v. Escaño (1965), the Court En Banc applied the adultery provisions as valid, holding that a wife’s remarriage after an invalid foreign divorce constituted adultery. The Court did not address the constitutionality of the penal provisions.

Recent Developments

Legislative proposals to decriminalize adultery and concubinage or to create a single, gender-neutral crime of marital infidelity have been filed in Congress but have not been enacted. As of 2026, the RPC provisions remain in force. The Supreme Court’s recent opinions signal judicial awareness of the constitutional infirmity, but no dispositive ruling has been issued. Web research confirms that enforcement remains infrequent and the laws are criticized as “largely un-enforced.” (Philippines: Information on adultery laws; Equality begins by ending the infidelity double standard)

Analysis

The differences between adultery and concubinage are fourfold:

1. Who is the principal offender: Adultery targets the married woman; concubinage targets the married man.
2. Actus reus: Adultery is consummated by a single act of sexual intercourse by the wife. Concubinage requires either cohabitation, scandalous intercourse, or maintenance of a mistress—a far heavier evidentiary burden.
3. Penalty: Adultery is punished with prisión correccional in its medium and maximum periods (2 years, 4 months, 1 day to 6 years), while concubinage is punished with prisión correccional in its minimum and medium periods (6 months, 1 day to 4 years, 2 months) for the husband, and mere destierro for the concubine.
4. Collateral consequences: A husband convicted of concubinage is subject to destierro for the concubine, but the husband himself faces imprisonment; in adultery, both offenders face equal imprisonment. The Tenchavez case demonstrates that a wife’s adultery can serve as a ground for legal separation, while a husband’s offense must qualify as concubinage—mere adultery by the husband is not a ground for legal separation under the Family Code (a distinction originally rooted in the Divorce Law, as in Francisco v. Tayao).

The present status under Philippine law is that both crimes remain in the Revised Penal Code and are enforceable, subject to the jurisdictional complaint requirement. No Supreme Court majority has declared them unconstitutional. However, the consistent expressions of concern from sitting justices, combined with legislative acknowledgment in R.A. 9262 and CEDAW obligations, strongly suggest that a constitutional challenge is viable. Practitioners should be aware that a future ruling could alter the landscape, but until then, the provisions are applied as written.

Section III — Action Plan & Evidence Guide

Recommended Strategy: A party seeking to file a complaint for adultery or concubinage must first ensure strict compliance with the jurisdictional requirement of Article 344. The offended spouse must personally swear to the complaint, name both guilty parties, and file it directly in court (after preliminary investigation, if required). Because these are private crimes, the State cannot initiate prosecution motu proprio. Death or incapacity of the offended spouse after filing does not abate the case, but any pardon or consent before filing is fatal.

Action Steps:

1. Draft and execute the complaint-affidavit — The offended spouse must personally execute a complaint-affidavit narrating all elements. The complainant must verify and swear to it before the prosecutor or a notary public. Ensure that both the spouse and the paramour/concubine are named.
2. File the complaint with the Office of the City/Provincial Prosecutor — The prosecutor will conduct a preliminary investigation. Only after finding probable cause may an information be filed in court.
3. Preserve the option for civil liability — The offended spouse may reserve the right to file a separate civil action for damages under Articles 21 and 2219 of the Civil Code, or may waive civil liability and file only the criminal case.
4. Document evidence immediately — In adultery cases, circumstantial evidence is critical. Secure photographs, communications, witness affidavits, hotel records, and birth certificates. In concubinage cases, evidence of cohabitation or the maintenance of a mistress in the conjugal dwelling is essential: proof of residence, utility bills, lease agreements, barangay certifications.

Evidence Checklist:

• Marriage certificate (NSO/PSA) — proves legal marriage
• Certified true copy of the complaint-affidavit — proves compliance with Article 344
• Birth certificate of child born from the illicit relationship — proves sexual intercourse or cohabitation (shows parentage and use of surname)
• Photographs and videos showing the accused together in intimate or domestic settings — circumstantial proof of sexual relations
• Testimony of disinterested witnesses (neighbors, household help) — corroborates cohabitation, scandalous circumstances, or the presence of a mistress in the conjugal dwelling
• Hotel receipts, travel records, lease contracts — establishes place and frequency of meetings
• Letters, text messages, social media posts — may demonstrate knowledge of marriage or the nature of the relationship
• Barangay blotter entries or police reports — if the offending spouse was caught in flagrante delicto, these records are crucial

⚠️ This is AI-generated legal research for reference only. It does not constitute legal advice. Consult a licensed Philippine attorney before making important legal decisions.

References

Legislation & Regulatory Issuances

• Revised Penal Code (RPC)
• Public Prosecution of the Crimes of Adulterio, Estupro, Rapto, Violacion, Calumnia, and Injuria, Abolishing the Right of Pardon by the Aggrieved Party in Such Cases, and Providing for a Special Civil Action for Damages Therein (Act No. 1773)

Case Law

• AUREL ANN CHUA-CHIBA, petitioner, vs. JIN CHIBA and MICHAEL LLONA, respondents., G.R. No. 277020 (19 May 2025)
• THE UNITED STATES vs. MARTINA BACAS, G.R. No. 5297 — US v. Bacas (19 October 1909)
• MILAGROS DONIO-TEVES and MANUEL MORENO, petitioners, vs. HON. CIPRIANO VAMENTA, JR., as Presiding Judge, Branch III, Court of First Instance, Negros Oriental, PABLO E. CABAHUG, as City Fiscal of Dumaguete, and JULIAN L. TEVES, respondents, G.R. No. L-38308 (26 December 1984)
• THE UNITED STATES vs. AGAPITO SERRANO and FAUSTINA ANANIAS, G.R. No. 9772 — US v. Ananias (16 October 1914)
• THE UNITED STATES vs. TORCUATA GOMEZ and RAMON NARCISO CORONEL, G.R. No. 4630 — US v. Coronel (19 December 1908)
• THE PEOPLE OF THE PHILIPPINE ISLANDS, plaintiff-appellee, vs. CONSOLACION INFANTE ET AL., defendants. CONSOLACION INFANTE, appellant, G.R. No. 36270 (31 August 1932)
• PEOPLE OF THE PHILIPPINES, petitioner, vs. HON. RICARDO M. ILARDE, in his capacity as Presiding Judge, CFI of Iloilo, Br. V, CECILE SANTIBAÑEZ and AVELINO T. JAVELLANA, respondents, G.R. No. L-58595 (10 October 1983)
• THE UNITED STATES vs. MARGARITA FELICIANO, G.R. No. 12724 — US v. Feliciano (10 August 1917)
• THE UNITED STATES vs. FABIANA LEGASPI and PAULINO PULONGBARET, G.R. No. 5110 — US v. Pulongbaret (19 August 1909)
• THE UNITED STATES vs. CECILIA MEMORACION and DALMACIO URI, G.R. No. 11371 — US v. Uri (1 August 1916)
• LAUREANO FERNANDEZ, petitioner, vs. THE HONORABLE JUDGE JAIME M. LANTIN and THE CITY FISCAL OF QUEZON CITY, respondents, G.R. No. L-44759 (17 December 1976)
• THE PEOPLE OF THE PHILIPPINE ISLANDS vs. AGAPITO FRANCISCO and JOSEFINA MANTELO, G.R. No. 29531 — People v. Mantelo (29 December 1928)
• FERNANDO MAULIT, petitioner-appellee, vs. DOMINGO SAMONTE, respondent-appellant, G.R. No. 34484 — Maulit v. Samonte (13 December 1930)
• THE PEOPLE OF THE PHILIPPINE ISLANDS, plaintiff-appellee, vs. PEDRO PITOC and MARCIANA DEL BASCO, defendants. PEDRO PITOC, appellant., G.R. No. 18513 (18 September 1922)
• EMILIANO CASTRO, JR., petitioner, vs. COURT OF APPEALS and PEOPLE OF THE PHILIPPINES, respondents, G.R. No. L-22159 — Castro, Jr. v. Court of Appeals (31 July 1968)
• THE UNITED STATES AND MARIA AUREUS, plaintiffs-appellees, vs. WENCESLAO MERCADO AND VICENTA REY, defendants-appellants, G.R. No. 3228 (3 August 1909)
• In re JUAN C. ISADA (16 November 1934)
• PASTOR B. TENCHAVEZ, plaintiff-appellant, vs. VICENTA F. ESCAÑO, ET AL., defendants-appellees, G.R. No. L-19671 — Pastor B. Tenchavez v. Vicenta F. Escaño (29 November 1965)
• JUANARIA FRANCISCO, plaintiff-appellant, vs. LOPE TAYAO, defendant-appellee, G.R. No. 26435 — Francisco v. Tayao (4 March 1927)
• FILOMENA DEL PRADO, plaintiff-appellant, vs. TIRSO DE LA FUENTE, defendant-appellee, G.R. No. 9274 — Del Prado v. De la Fuente (14 September 1914)
• PRECIOUSA CASTILLO-MACAPUSO vs. ATTY. NELSON B. CASTILLEJOS, JR. & ANONYMOUS vs. PRECIOUSA C. MACAPUSO, A.M. No. P-19-3985 & A.M. No. P-19-3986 (10 July 2019)
• G.R. No. 244657 - Dissenting Opinion - Lawphil — Valencia v. People (12 February 2024)
• G.R. No. 252739 - Concurring Opinion - Lawphil — XXX v. People (16 April 2024)
• Adultery, A333 Revised Penal Code - Legal Resource PH — legalresource.ph
• Philippines: Information on adultery laws, including enforcement ... — www.ecoi.net
• Equality begins by ending the infidelity double standard — mb.com.ph