Here’s a practical, Philippine-focused legal guide to what you (or your family) can do if a father’s mistress is harassing you. It’s written as an educational article—clear, comprehensive, and action-oriented. (This is not a substitute for individualized legal advice.)

Understanding the scenario

“Harassment” can take many forms: threatening calls or messages, public shaming posts, persistent unwanted contact (in person or online), doxxing, contacting your school/employer, following or stalking, humiliating remarks, or spreading false accusations. Your options depend on what exactly she did, how (offline vs. online), who the target is (spouse, child, other family members), and what proof you have.

Below are the main criminal, civil, and protective remedies available in the Philippines, plus step-by-step procedures, evidence tips, and strategic considerations—specifically for harassment by a father’s mistress.

Criminal remedies (possible charges)

1) Libel / Slander / Slander by Deed

When applicable: She publicly posts false imputations that injure your reputation (libel), tells lies orally (slander/defamation), or humiliates you through acts (slander by deed).
Where it happens:
- Libel → written/printed/online (including social media and group chats).
- Slander → spoken, in person or calls.
- Slander by deed → public gestures/acts causing dishonor.
Notes: Cyber libel (online) is punished under the Cybercrime law with a higher penalty. Truth is a defense only in specific circumstances (e.g., imputations made with good motives and for justifiable ends). Screenshots and platform logs are crucial.

2) Grave threats / Light threats

When applicable: She threatens harm (e.g., “I’ll hurt you,” “I’ll ruin your career,” “I’ll burn your house”). The gravity depends on the threat and whether it demands something.

3) Grave coercion

When applicable: She uses violence, intimidation, or threats to compel you to do something against your will (or to prevent you from doing something you legally may do), without legal authority.

4) Unjust vexation

When applicable: Annoying, disturbing, or irritating behavior without justification that falls short of other defined crimes (e.g., repeated nuisance calls, popping up at your workplace to embarrass you, spam harassment).

5) Alarm and scandal / Intrusion into privacy

When applicable: Tumultuous or scandalous disturbances in public; peeping/secret filming in places where you have an expectation of privacy may also violate special laws.

6) Gender-Based Sexual Harassment (Safe Spaces Act)

When applicable: If her acts are gender-based (catcalling, unwanted sexual comments, stalking, online sexual harassment, sexist threats/remarks), the Safe Spaces Act applies—in public spaces, online, workplaces, and educational institutions. Complaints may proceed administratively (e.g., with HR/school) and/or criminally.

7) Cyber harassment–related offenses (Cybercrime Prevention Act)

When applicable: Doxxing, cyberstalking, impersonation accounts, non-consensual sharing of private images, hacking/unauthorized access, cyber libel, data interference. Penalties are typically one degree higher than their offline counterparts.

8) Anti-Photo and Video Voyeurism Act

When applicable: Non-consensual capture or distribution of sexual images, even if privately obtained. Strong penalties and mandatory takedown can be pursued.

9) Child-specific protection (if minors are targeted)

When applicable: If the mistress harasses children (minors), consider the Special Protection of Children Against Abuse, Exploitation and Discrimination Act (child abuse includes psychological abuse), Anti-Bullying Act (for school-related bullying), Safe Spaces Act (minor victims), and pertinent provisions of the Revised Penal Code.

Important boundary: The Anti-VAWC (RA 9262) generally targets acts by a spouse/partner or former spouse/partner against a woman or her child. A mistress is not in a dating/sexual relationship with the offended woman; therefore, she is typically not a direct respondent under VAWC unless she conspires with or aids the partner in committing punishable acts (which is fact-specific and harder to prove). Don’t anchor your case on VAWC against the mistress alone unless a lawyer confirms your facts fit.

Family and morality crimes (contextual leverage)

Concubinage (against the father and paramour)

When applicable: Keeping a mistress in the conjugal dwelling, cohabiting with her elsewhere, or sexual intercourse under scandalous circumstances.
Effect on the mistress: She (the paramour) can be criminally liable (commonly destierro), but concubinage is about the sexual relationship, not harassment. Filing concubinage can be a parallel pressure point, but it does not directly punish harassment acts—use it alongside the harassment case if the elements fit.

Civil remedies (damages and injunctions)

1) Tort damages under the Civil Code

Articles 19, 20, 21 (“abuse of rights,” acts contrary to law/morals/good customs/public policy) and Article 26 (respect for dignity, personal privacy, and peace of mind) allow you to sue for moral, exemplary, and actual damages for harassment, humiliation, doxxing, or intrusion into family life—even if conduct is not a criminal conviction (civil proof is preponderance of evidence, i.e., “more likely than not”).
Article 33 allows a separate civil action for defamation, fraud, and physical injuries—independent of criminal cases.

2) Injunctions and restraining orders

You may file a civil action and apply for a Temporary Restraining Order (TRO) and Writ of Preliminary Injunction to stop the harassment (e.g., contacting you, coming near your home/school/work, posting or re-posting defamatory content, or contacting your kids/relatives).

3) Data privacy complaints (when applicable)

If she misuses personal data (unauthorized disclosure of addresses, phone numbers, photos), consider a complaint with the National Privacy Commission and parallel civil claims for damages.

Protective measures outside VAWC

Even if VAWC isn’t directly available against the mistress, you still have protective options:

Safe Spaces Act mechanisms: You can file with your barangay (for community/public harassment), with HR (workplace), with the school (education setting), and/or with law enforcement for criminal aspects.
Barangay Protection: While classic Barangay Protection Orders are a VAWC tool, barangays can still accept complaints (Katarungang Pambarangay) for mediation/conciliation in many non-serious offenses and community disputes, and can issue certifications useful for escalation.
No-Contact / Undertakings: In barangay mediation or civil suits, you can secure written undertakings (no approaching, no messaging, no social posts), breach of which strengthens later cases.

Where and how to file

A) For criminal complaints

Collect evidence (see checklist below).
Execute a detailed Sinumpaang Salaysay (sworn statement) naming specific acts, dates, times, platforms, witnesses.
File with the Office of the City/Provincial Prosecutor where the offense occurred (for cyber offenses, venue can hinge on where the complainant resides/where content was accessed).
Attach: IDs, screenshots (original file exports with URLs and timestamps), certifications (e.g., barangay blotter), NBI/PNP reports, and a device-based hash of files when possible.
Attend inquest (if warrantless arrest) or preliminary investigation (usual path). Respond to counter-affidavits, then await resolution and potential filing of Information in court.

B) For civil actions (damages/injunction)

Draft complaint stating unlawful acts and damage suffered under Civil Code provisions (Arts. 19–21, 26; Article 33 if defamation).
Apply for TRO/prelim injunction with verified complaint + bond, showing (a) clear right; (b) material/irreparable injury; (c) urgent necessity.
File in the Regional Trial Court with jurisdiction over the defendant’s residence or where the cause of action arose.

C) Administrative / quasi-judicial avenues

Workplace: File with HR/Committee on Decorum and Investigation (CODI) under the Anti-Sexual Harassment law and Safe Spaces Act (if conduct is gender-based or sexual in nature).
School: Report to the Committee on Decorum and Investigation (education-sector protocols), and, if the victim is a child, activate the Child Protection Committee.
National Privacy Commission: For privacy/data breaches; ask for takedown and damages.
Platform takedown: Use in-platform reporting for cyber abuse; preserve all data before takedown.

Evidence playbook (what wins or loses cases)

Preserve everything before confronting or asking for takedowns.

Digital: Full-page URL-visible screenshots; export message histories; download metadata (message IDs, headers, profile URLs); keep original files (not just cropped images).
Devices: Don’t factory-reset. Keep phones/laptops intact for potential forensic imaging.
Witnesses: Obtain sworn statements from people who saw posts/calls/encounters.
Pattern: A timeline showing frequency, escalation, and impact (panic attacks, missed work, school effects).
Damages: Medical/psychological consult notes, receipts (therapy, transport, security measures), HR memos, school letters.
Barangay/Police: Blotters and incident reports anchor your chronology.

Tip: Keep a harassment log (date/time, channel, what happened, witnesses/attachments). Judges and prosecutors value clear, chronological narratives.

Common fact patterns & best charges

Smear posts + doxxing on Facebook → Cyber libel, possibly data privacy violations, and civil damages (Arts. 19–21, 26).
Repeated threats by call/text → Grave/Light threats, unjust vexation; if demands are made, consider grave coercion.
Following you to school/work, waiting outside home → Stalking under the Safe Spaces Act (gender-based harassment), possibly alarm and scandal, plus civil injunction for no-contact.
Posting or sharing intimate images → Anti-Photo and Video Voyeurism Act, Cybercrime, civil damages, urgent takedown.
Harassing the children → Child abuse (psychological harm), Safe Spaces Act, school administrative actions, civil damages, and immediate safety plan.

Strategic sequencing (what to file first)

If safety risk is high: File police blotter + seek TRO/injunction (civil) or inquest if caught in flagrante; do platform takedowns only after evidence capture.
If reputational damage is ongoing online: Prioritize cyber libel complaint and injunction with specific takedown orders; add damages claims.
If you want leverage against the father too: Assess concubinage (if elements fit) as a separate track; it’s not about harassment but can shift dynamics in settlement/mediation.
If minors are affected: Move immediately with school/child-protection protocols and, if necessary, DSWD referrals.

Barangay Justice System and mediation

Many lesser offenses (e.g., unjust vexation) require prior barangay conciliation if parties live in the same city/municipality (exceptions apply: if the offense carries a higher penalty, parties live in different cities/municipalities, or there’s an urgent need for court action).
Even if not required, barangay complaints help document a pattern and often produce written no-contact undertakings.

Penalties & prescription (high-level)

Cyber libel / libel: generally heavier than simple oral defamation; cyber versions carry higher penalties.
Threats, coercion, unjust vexation: penalties vary from fines to short-term imprisonment depending on gravity.
Voyeurism, child abuse, cybercrime: stiffer penalties; courts take these seriously.
Civil damages: moral and exemplary damages can be significant if you prove malice, humiliation, and impact.
Prescription: Time limits to file vary by offense (e.g., libel is shorter than many other crimes); for civil torts, the general rule for quasi-delict is 4 years from discovery of the injury. When in doubt, file early.

Practical safety & documentation tips

Lock down privacy settings; avoid direct engagement; route communications via counsel when possible.
Tell trusted people at work/school/building security; give them a photo and no-entry/no-contact instruction if feasible.
Separate devices/accounts for evidence capture to avoid accidental deletion.
Medical/psych support: Consulting a psychologist/psychiatrist both helps you and strengthens claims for moral damages.
Do not harass back. Retaliatory posts can backfire legally.

When to get a lawyer (and what to bring)

If you’re filing criminal or civil cases or seeking injunctions, consult counsel early.
Bring: harassment log, screenshots with URLs/timestamps, witness list, medical notes, barangay/police blotters, and a clear objective (criminal punishment, damages, takedown, or all).

Quick decision tree

Is it online?
- Yes → Preserve evidence → Consider cyber libel, SS Act online harassment, privacy violations → File with prosecutor + civil damages + injunction; use platform takedown after preservation.
Are there threats or stalking?
- Yes → Threats/coercion + SS Act; seek police assistance and consider urgent TRO.
Are minors targeted?
- Yes → Trigger child-protection laws/protocols immediately.
Do the facts fit concubinage?
- Possibly → Consider filing separately, but don’t rely on it to address harassment acts.
Low-level nuisance but persistent?
- Start with barangay (conciliation/no-contact undertaking) + unjust vexation; escalate if it continues.

Key takeaways

A mistress who harasses can face multiple liabilities at once: criminal (libel, threats, coercion, cyber offenses), civil (damages and injunction), administrative (work/school), and even privacy penalties.
VAWC generally does not directly apply to the mistress (absent specific circumstances like conspiracy), so focus on defamation/threats/coercion/cybercrime/Safe Spaces routes.
Evidence discipline—preserve first, then act—is what turns a messy situation into a winnable case.
If children are involved, prioritize protection measures immediately.

If you want, tell me the specific behaviors she’s done (e.g., sample posts/messages, in-person incidents, whether minors were targeted), and I’ll map those facts to the strongest charge set and draft a complaint outline you can bring to counsel or the prosecutor.