Third-Party Adultery Lawsuit Defense Lawyer
Third-Party Adultery Lawsuit Defense Lawyer | What plaintiffs must prove, and how liability and damages are actually reduced
A third party who has an affair with a married person can be held liable for tortious infringement of the marital relationship under general tort law (민법 제750조), not under a specific "adultery" statute — criminal adultery was abolished in 2015. To win, the plaintiff (the spouse) must prove you knew, or should have known, that your partner was married, and that the marriage was harmed as a result. Many claims fail or are substantially reduced because this knowledge element, or the causal link to the marriage's breakdown, cannot be proven.
Third-Party Adultery Lawsuit Defense | What the plaintiff actually has to prove
Liability is not automatic just because a relationship happened. The legal basis is a general tort claim for infringement of the marital relationship, and it has specific elements the plaintiff must establish and you can challenge.
Legal basis: tort, not 'adultery'
Since adultery was decriminalized in 2015, there is no crime of adultery in Korea. Civil liability rests instead on general tort law: a person who intentionally or negligently infringes another's rights must compensate for the resulting damage (민법 제750조). Courts have applied this to third parties who interfere with the marital relationship, treating the marital bond as a protected interest.
Knowledge of the marriage is the key battleground
You are only liable if you knew, or negligently failed to realize, that the person was married at the time of the relevant conduct. If your partner concealed their marital status, actively lied about being divorced or separated, or presented convincing evidence of being single, this can be a full defense — not merely a mitigating factor. The burden of proving your knowledge or negligence generally falls on the plaintiff.
The marriage must already be substantively broken, or your conduct must have caused the harm
If the plaintiff's marriage had already effectively broken down before your relationship began — for example, the couple was already living separately with no intention of reconciling — Korean courts have held that a third party generally cannot be held liable, because there is no longer an intact marital relationship left to infringe. This is a frequently litigated and often decisive issue.
Third-Party Adultery Lawsuit Defense | How the compensation amount gets reduced even where some liability exists
Even where a court finds some liability, the amount awarded is highly fact-sensitive and is frequently reduced well below what the plaintiff originally demanded. Several factors are routinely raised on the defense side.
Degree of fault and duration of the relationship
Courts weigh how the relationship began, how long it lasted, whether it was a brief encounter versus a sustained relationship, and how actively each side pursued it. A short-lived or ambiguous relationship, or one where your partner was the primary instigator, typically supports a lower award.
State of the marriage at the time
Evidence that the marriage was already troubled — separate finances, sleeping arrangements, prior separation attempts, or the spouses' own conduct — can reduce the damages even if it does not fully eliminate liability, because it weakens the causal link between your conduct and the marriage's collapse (민법 제750조, 제763조에 의한 제396조 준용).
Plaintiff's own conduct and comparative fault
If the plaintiff spouse also had extramarital relationships, was abusive, or otherwise contributed to the marital breakdown, this comparative fault can be raised to reduce the award. Korean courts apply principles of comparative negligence by analogy in assessing the appropriate amount (민법 제396조 유추적용).
Statute of limitations
A damages claim of this kind must generally be brought within 3 years from when the plaintiff became aware of both the harm and the identity of the person liable, and in any case within 10 years of the wrongful act (민법 제766조). If the plaintiff delayed filing well beyond these periods, this can be raised as a complete defense.
Third-Party Adultery Lawsuit Defense | From receiving the complaint to resolution
We examine exactly what the plaintiff claims to prove — messages, photos, statements — and assess whether it actually establishes your knowledge of the marriage and harm to it.
We gather evidence of what you were told and shown about your partner's marital status, including messages, timeline of events, and any representations that they were single, separated, or divorcing.
Where possible, we look into whether the marriage had already broken down before your involvement, which can be decisive for liability, not just the damages amount.
We draft a formal response addressing lack of knowledge, an already-broken marriage, comparative fault of the plaintiff spouse, and statute of limitations where applicable.
Many of these cases resolve through court mediation (조정) at a reduced amount rather than a full trial judgment, particularly once liability is contested.
If the case proceeds to judgment, the court sets the amount based on all of the above factors; if settled, the terms are formalized and the case concludes.
Third-Party Adultery Lawsuit Defense | How defense costs are typically structured
An initial review of the complaint and evidence to assess exposure and viable defenses is billed separately from the retainer, and its scope depends on how much documentation must be reviewed.
Set based on the complexity of the factual dispute — particularly how much investigation is needed on the knowledge and marriage-breakdown issues — and whether the case is expected to go to full trial or settle early.
Where applicable, typically structured as a percentage of the amount by which the claimed damages are reduced from the plaintiff's original demand, rather than a fixed sum.
Court filing fees, service costs, and expenses for any additional fact-finding (e.g., document requests) are billed as incurred.
※ Costs vary depending on case complexity and specific circumstances; exact fees will be provided during consultation. No specific outcome is guaranteed.
Third-Party Adultery Lawsuit Defense | Self-Check for Third-Party Defendants
1️⃣ Knowledge of the marriage
- Did your partner ever tell you, in writing or otherwise, that they were single, separated, or getting divorced?
- Do you have any messages, photos, or documents that support what you were told about their marital status?
- Were there specific facts that made it reasonable for you to believe they were not married?
2️⃣ State of the marriage at the time
- Was the couple already living apart or in the process of divorcing when your relationship began?
- Is there any indication (from your partner or otherwise) that the marriage had already broken down?
- Did the plaintiff spouse ever mention their own affairs, separation attempts, or long-term estrangement?
3️⃣ Timeline and limitation period
- When did the plaintiff first find out about the relationship and your identity?
- Has more than 3 years passed since the plaintiff learned of the affair and who you are?
- Has more than 10 years passed since the relationship or conduct in question occurred?
4️⃣ Evidence and response strategy
- Have you preserved all relevant messages and records rather than deleting them?
- Have you filed a formal answer to the complaint within the deadline stated in the documents you received?
- Have you avoided making admissions or apologies in writing before consulting a lawyer?
