DISCLAIMER: This article is for general informational purposes only and does not constitute legal advice. Laws may change or be subject to varying interpretations, so it is advisable to consult a licensed attorney in the Philippines for advice specific to your situation.

Overview

In the Philippines, crimes relating to marital infidelity are primarily governed by the Revised Penal Code (RPC), which codifies two distinct offenses: adultery (committed by a married woman and her paramour) and concubinage (committed by a married man under specific circumstances with a woman who is not his wife). These crimes, found in Articles 333 and 334 of the RPC, reflect the traditional viewpoint on the sanctity of marriage under Philippine law. While there have been calls for reform—especially because of the perceived imbalance in how adultery and concubinage are defined and penalized—these provisions remain in effect.

Below is a comprehensive discussion of the legal definitions, elements, procedures, defenses, and key considerations surrounding adultery and concubinage in the Philippine context.

1. Adultery

1.1 Legal Basis

Article 333 of the Revised Penal Code (RPC) defines and penalizes adultery.

1.2 Definition of Adultery

Who can commit adultery?
- A married woman who engages in sexual intercourse with a man not her husband.
- The man (paramour) who has sexual intercourse with a married woman, knowing her to be married.
Essence of the Offense
- The act that constitutes adultery is voluntary sexual intercourse between a married woman and a man who is not her husband.
- Unlike concubinage (discussed below), no additional element—such as scandalous conduct, cohabitation, or maintenance of a mistress—is required. A single act of sexual intercourse can be sufficient to constitute adultery.

1.3 Elements of Adultery

To successfully prosecute a charge of adultery under Article 333, the following must be proven:

The woman is legally married.
She had sexual intercourse with a man who is not her husband.
The man with whom she had intercourse knew that she was married (if he is to be held liable as co-principal).
The prosecution must present evidence of the specific acts of adultery (the dates and circumstances), not merely a general suspicion.

1.4 Penalty for Adultery

The penalty under the Revised Penal Code for both guilty parties (the married woman and her paramour) is prisión correccional in its medium and maximum periods (i.e., from 2 years, 4 months, and 1 day to 6 years).

1.5 Who Can File the Case

Adultery is classified as a private crime. Only the offended spouse (i.e., the legal husband of the adulterous wife) can initiate the criminal action.
The complaint must include both the wife and the paramour as respondents; failure to include one typically leads to the dismissal of the case unless there is a valid cause for not including the other party (e.g., death or unknown identity).

1.6 Effect on Parental Authority or Property

A conviction of adultery in itself does not automatically terminate marriage or parental authority.
However, it can be used as grounds in civil or family law cases (e.g., psychological incapacity claims under the Family Code, or child custody disputes), although each matter is still assessed under its own legal provisions.

2. Concubinage

2.1 Legal Basis

Article 334 of the Revised Penal Code (RPC) defines and penalizes concubinage.

2.2 Definition of Concubinage

Who can commit concubinage?
- A married man who commits certain acts with a woman not his wife (the “concubine”).
Essence of the Offense
- Concubinage punishes specific scenarios of marital infidelity by the husband that go beyond a single act of sexual intercourse.
- It requires proof of more habitual or scandalous conduct, such as maintaining a mistress in the conjugal home, cohabiting in another place, or engaging in scandalous sexual intercourse.

2.3 Acts Constituting Concubinage

Under Article 334, a married man is liable for concubinage when he:

Keeps a mistress in the conjugal dwelling; or
Cohabits with a woman not his wife in any other place; or
Has sexual intercourse under scandalous circumstances with a woman who is not his wife.

2.4 Elements of Concubinage

To successfully prosecute a charge of concubinage, the following must be proven:

The man is legally married.
He either:
- Maintains a mistress in the conjugal dwelling;
- Cohabits with her in any other place; or
- Has scandalous sexual intercourse with her.
The woman involved (the concubine) must know that the man is married.

2.5 Penalty for Concubinage

The penalty for the married man (if convicted) is prisión correccional in its minimum and medium periods (i.e., 6 months and 1 day to 4 years and 2 months).
The penalty for the concubine is destierro (banishment). This means she may be required to stay away from a specified place (usually a certain radius away from where the offended spouse resides or other areas determined by the court).

2.6 Who Can File the Case

Concubinage is also a private crime. Only the offended spouse (i.e., the legal wife of the husband engaged in concubinage) can initiate the criminal action.
As with adultery, the complaint must ordinarily include both the husband and the concubine.

3. Procedural Aspects

3.1 Jurisdiction and Venue

Cases of adultery and concubinage are filed before the Regional Trial Court (RTC) with the appropriate jurisdiction, typically the place where the offense was committed or where any of the essential elements occurred.

3.2 Period to File the Complaint

Like other criminal actions, there is a prescriptive period. Under Article 90 of the RPC, crimes punishable by prisión correccional generally prescribe in 10 years. In practice, since adultery and concubinage are private crimes, swift legal action is often recommended once there is sufficient proof; undue delay can raise doubts about the authenticity of the charges.

3.3 Requirement of Evidence

The burden of proof is on the prosecution, who must demonstrate beyond reasonable doubt that the offense was committed.
Evidence often includes text messages, photos, testimony from witnesses, or admissions. However, mere suspicion, rumor, or circumstantial evidence without clear proof of actual sexual intercourse or cohabitation typically will not suffice.

3.4 Reconciliation

If the offended party pardons or consents to the act(s) complained of, the criminal liability may be extinguished. For instance, the Revised Penal Code states that the offended party’s pardon before the filing of the complaint bars prosecution.
If the parties reconcile (i.e., express or implied condonation), the prosecution might fail.

4. Comparison: Adultery vs. Concubinage

Aspect	Adultery	Concubinage
Who Commits	Married woman & her paramour	Married man & his concubine
Acts Punished	A single act of sexual intercourse	1) Keeping a mistress in the conjugal home 2) Cohabitation with her 3) Scandalous sexual intercourse
Penalty	Prisión correccional (medium and maximum periods)	Prisión correccional (minimum and medium periods) for the husband, destierro for the concubine
How Filed	Private crime; only offended spouse can file	Private crime; only offended spouse can file
Inclusion of Parties	Must include wife and paramour	Must include husband and concubine
Proof Required	Must prove specific acts of intercourse; single act suffices	Must prove cohabitation, maintenance of mistress, or scandalous intercourse (habitual or in a scandalous manner)

One notable critique is that adultery can be proven by one act of sexual intercourse involving the wife, while concubinage requires a series of acts or more elaborate conditions to penalize the husband’s infidelity. This perceived imbalance has long been a subject of debate among legal scholars, policy-makers, and activists seeking to amend the law.

5. Civil Implications and Related Family Law Issues

Legal Separation, Annulment, and Declaration of Nullity
- Marital infidelity (adultery or concubinage) can be cited as a ground for legal separation under Article 55 of the Family Code.
- For annulment or declaration of nullity, adultery or concubinage alone is not an automatic ground, but it could be used to demonstrate psychological incapacity or other grounds depending on the circumstances.
Effects on Child Custody and Support
- In determining child custody, Philippine courts emphasize the best interest of the child. Adultery or concubinage by itself does not necessarily bar a spouse from obtaining custody unless it can be shown that such behavior compromises the child’s welfare.
- Child support obligations remain, irrespective of whether a spouse committed adultery or concubinage.
Property Relations
- Infidelity does not automatically deprive an offending spouse of property rights acquired during marriage. However, it may impact claims of damages in civil law, especially when one spouse’s infidelity has clearly caused harm to the other.

6. Social Context, Criticisms, and Proposed Reforms

Criticisms of Gender Inequality
- There has been strong criticism that the law discriminates against women, since adultery punishes a single act of infidelity by the wife, whereas concubinage requires proof of cohabitation, scandalous circumstances, or maintaining a mistress.
- Critics argue that this disparity is rooted in historical biases aimed at preserving paternal certainty of offspring rather than promoting genuine equality between spouses.
Proposed Legislative Changes
- Various bills have been filed in the Philippine Congress seeking to amend Articles 333 and 334 of the RPC to remove gender distinctions or modernize the law.
- Some proposals suggest decriminalizing adultery and concubinage altogether or replacing them with a single, gender-neutral crime of marital infidelity.
- As of this writing, however, no major reform of these provisions has been enacted.
Evolving Judicial Attitudes
- Courts have recognized potential abuses of these provisions when used as tools of harassment in marital conflicts.
- There has been an increasing emphasis on protecting constitutional and privacy rights, though such rights typically yield where the evidence of infidelity is overwhelming and properly obtained.

7. Defenses and Mitigating Circumstances

Lack of Knowledge
- The paramour or concubine can claim they had no knowledge that the person was married if, in fact, the other party concealed their true marital status.
Pardon and Condonation
- An express pardon (in writing) by the offended spouse or proof of implied pardon (e.g., continued cohabitation and marital relations after knowledge of infidelity) can bar prosecution.
Consent
- If the offended spouse consented to the adulterous or concubinous relationship from the outset, liability may be negated.
Insufficiency of Evidence
- For adultery, failure to prove actual sexual intercourse (or to identify the specific acts) can lead to acquittal.
- For concubinage, lack of proof of cohabitation, scandalous circumstances, or keeping a mistress is a common defense.

8. Practical Tips and Reminders

Consult an Attorney
- If you believe you have grounds to file a criminal complaint for adultery or concubinage, consult a lawyer to assess the strength of the evidence and to comply with procedural requirements.
Gather Clear Evidence
- Photographic evidence, text messages, emails, and witness statements are commonly used to prove the factual elements. However, ensure these are lawfully obtained.
Consider Civil or Family Remedies
- Aside from or in conjunction with criminal prosecution, consider filing for legal separation, or consult on whether an annulment or declaration of nullity is appropriate for your situation.
Timing and Prescription
- Do not unduly delay if you intend to file charges. Private crimes still carry prescriptive periods, and courts may look with suspicion on charges filed long after the alleged infidelity occurred.
Consider Reconciliation or Alternative Resolution
- Marital disputes are often highly emotional, and the process of criminal litigation can be lengthy, expensive, and traumatic for all involved (including any children). Some couples opt for reconciliation, counseling, or simply a civil remedy instead of criminal prosecution.

Conclusion

Adultery and concubinage remain part of the Philippine legal landscape, reflecting traditional concepts of marital fidelity and morality. They are private crimes, initiated only by the offended spouse, and have specific elements and penalties outlined under Articles 333 and 334 of the Revised Penal Code. The disparities in how adultery and concubinage are defined—particularly the requirement of a single act for adultery versus more habitual or scandalous conduct for concubinage—have long been the subject of debate and calls for reform.

Nevertheless, these laws continue to be enforced, and any spouse considering filing charges must carefully gather sufficient evidence and comply with legal requirements. Given the complexity and emotional stakes, seeking the guidance of a qualified attorney is essential to protect one’s rights and navigate any possible civil, criminal, or family-related remedies.