在日本的婚戀或交友網站上偽造身分，尤其是刻意隱瞞自己「已婚」的事實，並在此基礎上與他人發生性行為，確實潛藏相當高的法律風險。不過，這類案件在日本的法律處理上，必須清楚區分「民事責任」與「刑事責任」兩種不同層次，否則很容易誤以為只要涉及欺騙就一定會被判刑或罰款，這其實並不完全正確。

在實務上，最常見、也是風險最高的，並非刑事處罰，而是民事上的損害賠償責任。日本法院近年逐漸確立一項重要的法律概念，即所謂的「貞操權」或「性自主決定權」。這項權利並不限於傳統意義上的貞潔，而是強調個人有權基於正確資訊，自主決定是否、以及與誰發生性行為。若一方在交友平台上透過刻意隱瞞已婚身分，甚至搭配虛構單身背景、學歷、職業或人生規劃，使對方在錯誤認知的情況下同意建立親密關係，法院往往會認定這已構成對貞操權的侵害。

在近年的判決趨勢中，這類民事慰謝料的金額已逐步明確化。以 2025年前後大阪地方法院與東京地方法院的判例為例，賠償金額多半落在50萬至200萬日圓之間，約相當於新台幣10萬至40萬元不等。情節較輕、欺騙手法單一、交往時間不長的案件，可能判賠約50萬至60萬日圓；但若行為人長期以「獨身」為前提發展關係，甚至談及結婚承諾、同居計畫或未來人生規劃，法院對其惡質性的評價會顯著提高，判賠金額也可能上升至150萬甚至200萬日圓。這類判決在日本司法實務中，已逐漸形成穩定的裁量區間。

至於是否會涉及「判刑」或刑事責任，則必須更加審慎區分。單純在交友軟體上偽造或隱瞞身分，本身通常不直接構成刑法犯罪。日本刑法並未將「感情或婚戀詐欺」一概入罪，除非行為人的目的已超出感情交往的範圍，轉而涉及明確的財產侵害。例如，若以假單身、假結婚為手段，誘使對方交付金錢、支付生活費、投資款或高額贈與，就可能構成刑法第 246 條的詐欺罪，最重可判處 10 年有期徒刑。換言之，是否進入刑事責任的關鍵，不在於「有沒有說謊」，而在於「是否藉此騙取財物」。

至於性犯罪層面的刑事責任，門檻則更高。只有在欺騙手段達到使對方喪失反抗能力、判斷能力，或處於意識不清、無法自由做出性同意的狀態時，才有可能構成強制性交或相關罪名。單純隱瞞已婚身分、即便在道德與民事責任上受到嚴厲譴責，通常仍不會被日本刑法視為性犯罪。

除了司法層面的風險外，交友平台本身的規範與衍生後果也不容忽視。多數日本主流婚戀網站與App，例如 Pairs、Omiai等，都在使用條款中明確禁止虛假身分、偽造婚姻狀況或不實個人資訊。一旦遭到檢舉並查證屬實，行為人通常會面臨立即退會、永久停權，且無法再以相同身分重新註冊的處分。在情節嚴重、引發媒體或社群關注的情況下，平台營運方甚至可能以商譽受損為由，保留向當事人請求民事賠償的權利。

值得注意的是，近年日本已出現專門處理「交友軟體偽裝單身」案件的律師與法律諮詢服務。隨著數位鑑識技術成熟，透過IP紀錄、手機門號、支付紀錄或平台配合調查，受害者取得對方真實身分並提起訴訟的難度正在降低。這也意味著，過去被認為「很難被追究」的行為，正逐步轉變為高風險行為。

總體而言，在日本婚戀平台上隱瞞已婚身分並非只是道德爭議，而是一個實際可能付出高額金錢代價、甚至在特定情況下引發刑事責任的法律問題。隨著判例累積與社會觀感轉變，相關風險只會愈來愈明確，而非逐漸淡化。

On Japanese dating or matchmaking websites, falsifying one’s identity—especially deliberately concealing the fact that one is already married—and then engaging in sexual relations with another person does indeed carry significant legal risks. However, how the law responds depends on a clear distinction between civil liability and criminal liability. Many people mistakenly assume that any form of deception will automatically result in a criminal conviction or fines, but that is not entirely accurate under Japanese law.

In practice, the most common and most serious consequence is civil liability, not criminal punishment. In recent years, Japanese courts have increasingly recognized an important legal concept known as the “right to sexual autonomy” (also referred to as the right to chastity). This right does not simply refer to traditional notions of sexual purity; rather, it emphasizes an individual’s right to decide freely, based on accurate information, whether to engage in sexual relations and with whom. If one party intentionally conceals a married status on a dating platform—often accompanied by fabricated claims of being single, or false information about education, occupation, or life plans—thereby inducing the other party to consent to intimacy under false assumptions, courts are likely to find that this constitutes an infringement of the other party’s sexual autonomy.

Recent judicial trends have clarified the typical range of compensation (emotional distress damages) in such civil cases. Based on rulings around 2025 from district courts in Osaka and Tokyo, compensation generally falls between 500,000 and 2,000,000 yen, roughly equivalent to NTD 100,000 to 400,000. In relatively mild cases—where the deception is limited, the relationship is short, and the harm is considered less severe—awards may be around 500,000 to 600,000 yen. However, where the deception is prolonged or particularly malicious, such as maintaining a long-term relationship under the pretense of being single, discussing marriage, cohabitation, or long-term life plans, courts tend to view the conduct far more harshly, with compensation rising to 1.5 million or even 2 million yen. These amounts are increasingly becoming a stable benchmark in Japanese case law.

As for criminal liability, the threshold is much higher. Simply falsifying or concealing personal information on a dating app does not, by itself, usually constitute a criminal offense. Japanese criminal law does not broadly criminalize “romantic” or “marital” deception. Criminal responsibility typically arises only when the conduct goes beyond emotional manipulation and involves clear financial harm. For example, if someone uses a false single status or fake marriage promises to obtain money—such as living expenses, investments, loans, or expensive gifts—the conduct may constitute fraud under Article 246 of the Japanese Penal Code, which carries a maximum penalty of up to 10 years’ imprisonment. In other words, the key issue is not whether a lie was told, but whether that lie was used to unlawfully obtain property or financial benefits.

With regard to sexual offenses, the bar is even higher. Criminal charges such as forcible sexual assault generally apply only when deception deprives the victim of the ability to resist or make a free and conscious decision—for example, when the victim is rendered unconscious, incapacitated, or otherwise unable to give valid consent. Mere concealment of a married status, even if morally reprehensible and civilly actionable, is usually not treated as a sexual crime under Japanese criminal law.

Beyond court proceedings, platform rules and secondary risks should not be overlooked. Most major Japanese dating apps and matchmaking services, such as Pairs and Omiai, explicitly prohibit false information or misrepresentation of marital status in their terms of service. Once reported and verified, offenders typically face immediate account termination and permanent bans, often without the possibility of re-registration under the same identity. In particularly serious cases that damage the platform’s reputation, operators may even reserve the right to pursue civil claims for commercial or reputational harm.

It is also worth noting that Japan has seen the rise of legal services specializing in cases involving “pretending to be single” on dating apps. As digital forensics become more sophisticated, victims are increasingly able to identify perpetrators through IP addresses, phone numbers, payment records, and cooperation from platform operators. As a result, behavior that was once considered difficult to trace or enforce is rapidly becoming much riskier.

Overall, concealing a married status on Japanese dating platforms is not merely a moral issue. It is a legally actionable act that can result in substantial financial liability and, in specific circumstances, even criminal prosecution. As court precedents accumulate and social attitudes continue to shift, these risks are becoming clearer and more firmly established rather than fading away.