Concubinage is a criminal offense in the Philippines defined and penalized under Article 334 of the Revised Penal Code (Act No. 3815, as amended). It is classified as a crime against chastity, specifically addressing marital infidelity by a married man. This provision is paired with Article 333 on adultery, which applies to married women. Both are considered private crimes under Article 344 of the RPC.

Definition and Elements of Concubinage

Concubinage is committed by any husband who:

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

For the offense to be consummated:

The offender must be a legally married man.
There must be a mistress or woman involved in one of the three modes.
In the second and third modes, there must be evidence of sexual relations or cohabitation.
The concubine (the woman) is also liable if she has knowledge that the man is married.

The three modes are alternative; commission of any one suffices. “Keeping a mistress in the conjugal dwelling” typically implies maintaining the illicit relationship within the marital home, often not requiring explicit proof of sexual acts if the cohabitation is established. “Scandalous circumstances” in the second mode means the act is done in a manner that causes public scandal or notoriety. The third mode involves living together as if husband and wife elsewhere.

Liability of the Concubine

The woman involved shall suffer the penalty of destierro. Her liability is not independent; she is punished as a necessary participant or accomplice in the husband’s crime, but only if it is proven that she knew of his married status at the time of the relationship.

Penalties

For the husband (concubinage): Prision correccional in its minimum and medium periods. This translates to a range of six (6) months and one (1) day to four (4) years and two (2) months of imprisonment.
For the concubine: Destierro, which involves banishment from a specified place (usually the residence of the offended party or the locality) for a period ranging from six (6) months to six (6) years, during which the offender is prohibited from entering the designated area.

These penalties are principal penalties. Accessory penalties may include suspension of parental authority or disqualification from certain rights depending on the circumstances. The exact penalty may be adjusted based on attending circumstances (mitigating, aggravating) under the RPC rules.

Prosecution of the Crime

Concubinage, like adultery, is a private crime. Under Article 344 of the Revised Penal Code, it shall not be prosecuted except upon a complaint filed by the offended spouse. The complaint must be filed within the prescriptive period (generally 10 years for these crimes, but subject to rules on discovery).

Key rules:

The offended party (the legal wife) must personally file the complaint.
If the wife consents to or pardons the act (express or implied condonation), the criminal action is extinguished.
Pardon must occur before the institution of the criminal action.
The action cannot be prosecuted if both spouses are guilty of infidelity or if there is mutual forgiveness.
The concubine is included in the complaint against the husband.

Prosecution is de oficio only in the sense that once the complaint is filed, the State pursues it, but initiation requires the private complainant.

Related Civil Aspects

Under the Family Code of the Philippines (Executive Order No. 209, as amended):

Concubinage constitutes sexual infidelity, which is a ground for legal separation under Article 55.
It may also impact property regimes (e.g., forfeiture of share in conjugal properties in some cases), support obligations, and custody of children.
In nullity of marriage cases under Article 36 (psychological incapacity), chronic infidelity may be indicative but is not itself a ground for nullity.
The offended spouse may file for damages in civil court separately or as implied in family cases.

Philippine law does not recognize absolute divorce for non-Muslim citizens (except through annulment or nullity), making legal separation the primary remedy for such marital issues.

Distinction from Adultery and Other Crimes

Adultery (Art. 333 RPC): Committed by a married woman who has sexual intercourse with a man not her husband. Both the wife and her paramour are liable with prision correccional in its medium and maximum periods (2 years, 4 months and 1 day to 6 years). It is simpler: only requires one act of sexual intercourse.
Concubinage requires more ongoing or scandalous conduct and has lower penalties for the principal offender.
Bigamy (Art. 349): Involves contracting a second marriage while the first is subsisting – different from mere cohabitation.
Not to be confused with “concubinage” in a civil sense or other jurisdictions.

Constitutional and Practical Considerations

The provisions have been critiqued for gender disparity (harsher or different treatment), but remain in effect as they are rooted in traditional views on marital obligations. Prosecutions are relatively rare due to social, cultural, and familial considerations, often resolved privately or through civil remedies. Evidence typically includes witness testimonies, documents proving marriage, and proof of the illicit relationship (photos, communications, cohabitation evidence).

In all cases, the presumption of innocence applies, and guilt must be proven beyond reasonable doubt.