Query: Can the wife file a case against me for having an affair with her husband, even though they have been separated for over 15 years?

In the Philippines, the legal implications of engaging in a relationship with a married individual can be severe, even if the couple has been separated for a significant period. Under Philippine law, particularly the Revised Penal Code, adultery can be committed by a married woman and her partner if the act of sexual intercourse occurs under scandalous circumstances.

Understanding Adultery:

Adultery is defined under Article 333 of the Revised Penal Code of the Philippines. For the wife's paramour to be held liable, it is not necessary for him to be married. The crime of adultery can be prosecuted if the husband initiates the complaint.
It’s important to note that the law does not require the married couple to be living together; hence, separation (whether legal or de facto) does not dissolve the marriage bond nor does it legally permit the parties to engage in relationships with other people.

Criteria for Filing Adultery Charges:

Proof of Sexual Intercourse: Concrete evidence or substantial proof is required to show that sexual intercourse has occurred between the married woman and her partner.
Scandalous Circumstances: The acts must be committed under circumstances which are considered scandalous. This is a subjective criterion and can vary based on societal standards and personal perceptions.

Legal Separation and Its Implications:

Being separated without a legal decree (de facto separation) does not alter the marital status of the individuals, which means the obligations and legal bounds of marriage still apply.
Only a court-ordered annulment or a legally recognized dissolution of marriage can permit legally married individuals to enter into other relationships without risking legal consequences.

Defenses and Considerations:

If accused of adultery, one potential defense is the lack of knowledge about the marital status of the partner. However, this is often difficult to prove and does not guarantee dismissal of charges.
The long duration of separation may be considered in mitigating circumstances but generally does not absolve the liability for adultery.

Conclusion: Yes, the wife can legally file an adultery case against the partner of her estranged husband, regardless of the length of their separation. Individuals involved in such relationships should seek legal advice to understand their rights and potential legal liabilities fully. The laws regarding adultery are strict in the Philippines, and those found guilty can face severe penalties, including imprisonment. Therefore, understanding and respecting the legal boundaries set forth by marital status is crucial to avoid serious legal repercussions.