Introduction

In the Philippines, adultery and concubinage are criminal offenses rooted in the country's colonial legal history and enshrined in the Revised Penal Code (RPC) of 1930. These crimes reflect traditional views on marital fidelity, emphasizing the protection of the family unit. Adultery pertains to infidelity by a married woman, while concubinage addresses similar acts by a married man, though with notably different standards and penalties. These are considered "private crimes," meaning they can only be prosecuted upon the complaint of the offended spouse, and they carry implications not only for criminal liability but also for civil matters such as annulment or legal separation.

This article provides a comprehensive overview of these offenses in the Philippine context, including their definitions, elements, penalties, procedural aspects for filing a case, evidentiary requirements, defenses, and related legal considerations. It is essential to note that while these laws remain in force, there have been ongoing discussions about their gender bias and relevance in modern society, though no major reforms have altered their core provisions as of the last known legal framework.

Historical and Legal Background

The provisions on adultery and concubinage trace back to Spanish colonial law, specifically the Penal Code of 1884, which was later adopted and modified in the RPC (Act No. 3815). Article 333 defines adultery, and Article 334 defines concubinage. These laws were influenced by Catholic moral teachings prevalent during the Spanish era, viewing marriage as a sacred institution. Unlike many jurisdictions that have decriminalized adultery, the Philippines retains these as punishable acts, aligning with its conservative family-oriented legal system under the Family Code of 1987.

Critics argue that the laws exhibit gender disparity: adultery is easier to prove and harsher on women, while concubinage requires more stringent proof for men. Despite calls for repeal or amendment—often citing equality under the 1987 Constitution—these articles persist, with the Supreme Court upholding their validity in cases like People v. Zapata (1951) and People v. Schneckenburger (1938).

Definitions and Distinctions

Adultery (Article 333, RPC)

Adultery is committed by any married woman who shall have sexual intercourse with a man not her husband, and by the man who has carnal knowledge of her, knowing her to be married, even if the marriage be subsequently declared void.

Key points:

It applies exclusively to the married woman and her paramour.
The act must involve sexual intercourse; mere romantic involvement or emotional infidelity does not suffice.
The paramour's knowledge of the woman's marital status is crucial; ignorance may absolve him.
If the marriage is void ab initio (from the beginning), the crime may still stand if the parties believed it valid at the time.

Concubinage (Article 334, RPC)

Concubinage is committed by any husband who shall keep a mistress in the conjugal dwelling, or shall have sexual intercourse, under scandalous circumstances, with a woman who is not his wife, or shall cohabit with her in any other place.

Key points:

It applies only to the married man and his mistress.
Three modes of commission:
1. Keeping a mistress in the conjugal home (e.g., living together openly).
2. Sexual intercourse under scandalous circumstances (e.g., public displays causing outrage).
3. Cohabitation elsewhere (habitual living together as husband and wife).
Unlike adultery, isolated acts of intercourse without the additional elements do not constitute concubinage.
The mistress must be aware of the man's marriage for her liability.

Distinctions:

Adultery requires only one act of intercourse, while concubinage demands ongoing or scandalous behavior.
Penalties for adultery are stricter (see below).
Adultery criminalizes the woman primarily, reflecting historical patriarchal norms, whereas concubinage focuses on the man's actions.

Elements of the Crimes

For adultery:

The offender is a married woman.
She engages in sexual intercourse with a man not her husband.
The man knows she is married.

For concubinage:

The offender is a married man.
He commits one of the three acts: keeping a mistress at home, scandalous intercourse, or cohabitation elsewhere.
The woman knows he is married (for her co-liability).

In both cases, the marriage must be valid or at least presumed valid. Bigamous marriages can complicate matters, as seen in People v. Nepomuceno (1960), where subsequent marriages do not erase liability for prior acts.

Penalties

Adultery

Both the wife and her paramour: Prisión correccional in its medium and maximum periods (2 years, 4 months, and 1 day to 6 years).
If the paramour is unaware of the marriage: No liability.

Concubinage

The husband: Prisión correccional in its minimum and medium periods (6 months and 1 day to 4 years and 2 months).
The mistress: Destierro (banishment from a certain place for 6 months and 1 day to 6 years).
Lighter penalties reflect the law's leniency toward men.

Aggravating circumstances (e.g., abuse of authority) may increase penalties under general RPC rules. Mitigating factors, like voluntary surrender, can reduce them.

Who Can File and Prescription Period

These are private crimes under Article 344 of the RPC, prosecutable only by the offended spouse. Key rules:

Only the husband can file for adultery against his wife and her paramour.
Only the wife can file for concubinage against her husband and his mistress.
If the offended spouse is incapacitated, guardians or ascendants may file.
Pardon by the offended spouse (express or implied, e.g., continued cohabitation) extinguishes the action.
Prescription: 15 years from discovery of the offense (Article 90, RPC), as these are afflictive penalties.

No public prosecutor can initiate without the spouse's complaint, emphasizing the personal nature of the offense.

How to File a Criminal Case: Step-by-Step Procedure

Filing a case for adultery or concubinage involves a specific process under Philippine criminal procedure rules (Rules of Court, Rule 110). Below is a detailed guide:

1. Gather Evidence

Essential for probable cause. Types include:
- Witness testimonies (e.g., eyewitnesses to acts).
- Documentary evidence: Hotel receipts, messages, photos, or videos showing intercourse/cohabitation.
- Confessions or admissions.
- For adultery: Proof of marriage (certificate) and act (e.g., birth of a child from the affair as presumptive evidence).
- For concubinage: Evidence of scandal or cohabitation (e.g., lease agreements, neighbor affidavits).
Note: Circumstantial evidence suffices if it leads to moral certainty (People v. Acuram, 2000). Direct proof of intercourse is rare, so chain of events is key.

2. File a Complaint-Affidavit

Draft a sworn complaint-affidavit detailing the facts, elements, and evidence.
File at the Office of the City or Provincial Prosecutor (Fiscal) in the place where the crime occurred or where the accused resides.
Include: Names of accused, description of acts, date/place, witnesses, and attachments.
Pay filing fees (minimal for criminal cases).

3. Preliminary Investigation

The prosecutor conducts an investigation: Subpoenas the accused for counter-affidavits, replies, and clarifications.
Determines probable cause. If found, files an Information in court; if not, dismisses the case.
Timeline: Usually 60-90 days, but can extend.

4. Court Proceedings

Upon filing of Information, the court issues a warrant of arrest (if probable cause affirmed).
Arraignment: Accused pleads guilty/not guilty.
Pre-trial: Agreements on stipulations, evidence marking.
Trial: Presentation of evidence, cross-examinations. Prosecution proves guilt beyond reasonable doubt.
Decision: Conviction or acquittal. Appeals possible to Court of Appeals, then Supreme Court.

5. Bail and Provisional Remedies

Accused may post bail (amount set by court, based on penalty).
Offended spouse may seek civil damages simultaneously (e.g., moral damages under Article 2219, Civil Code).

6. Special Considerations

If abroad: Extradition possible if treaty exists.
Multiple acts: Each act may be a separate offense, but often consolidated.
Effect on family: Filing may lead to legal separation (Family Code, Article 55), with custody and support implications.

Evidentiary Requirements and Challenges

Proof must establish all elements beyond reasonable doubt. Common challenges:

Privacy: Acts often occur in secret, making direct evidence scarce.
Digital evidence: Texts/emails admissible if authenticated (Rules on Electronic Evidence).
DNA tests: For paternity in related civil suits, but not mandatory for criminal case.
Hearsay: Generally inadmissible unless exceptions apply.

Cases like People v. Serrano (2010) highlight that opportunity and predisposition can infer guilt.

Defenses and Extenuating Circumstances

Lack of knowledge of marriage.
Absence of sexual intercourse (for adultery) or required modes (for concubinage).
Pardon by spouse: Bars prosecution if given before filing.
Insanity or mistake of fact.
Prescription or double jeopardy.
Constitutional challenges: Arguments on equal protection have failed, as in Estrada v. Escritor (2003), which dealt with related issues but upheld the laws.

Related Legal Implications

Civil aspects: Grounds for legal separation (not absolute divorce, as Philippines lacks it except for Muslims or foreigners). Affects property division, child custody.
Annulment: Infidelity alone not a ground; must tie to psychological incapacity (Article 36, Family Code).
Child legitimacy: Child born during marriage presumed legitimate, rebuttable by proof of non-access.
VAWC Act (RA 9262): Overlaps if infidelity involves violence or economic abuse.
International aspects: Filipinos abroad subject to RPC if act committed outside but against Philippine laws (Article 2).

Conclusion

Adultery and concubinage remain potent tools for addressing marital infidelity in the Philippines, underscoring the legal system's emphasis on family integrity. However, their gendered framework invites scrutiny for fairness. Filing a case requires careful preparation, as it irrevocably impacts personal lives. Consulting a lawyer is advisable to navigate nuances, ensure compliance, and explore alternatives like mediation under the Family Code. While these laws endure, societal shifts may eventually prompt reform, but for now, they stand as a reminder of the intersection between morality and criminal justice.