Insights

Can Ningbo Call the Police to Catch the House Derailment

Ningbo Author：LuXu WANG

Ms. Li suspects her husband has been staying in a hotel with a third party and wants to call the police to have them come and “catch them in the act.” She wonders whether reporting it to the police will actually be effective and how the police would handle the situation if they arrived. First of all, the conclusion is that the simple cheating of opening a house belongs to the moral and civil category and does not belong to the jurisdiction of the public security organ. The alarm for "catching rape" usually does not get a response-the public security organ deals with illegal and criminal acts: if the opening of a house involves prostitution and whoring, it is a public security violation and can be reported to the public security organ or prosecuted to the people's court. However, if one of the husband and wife voluntarily open a house with the heterosexual outside marriage and there is not involved, the police will not get involved in "catching the rape". The proper course of action for protecting one’s rights is not to call the police, but rather to gather evidence in accordance with the law and then assert those rights in divorce proceedings. In this paper, the current "Public Security Administration Punishment Law" and "Criminal Law", the "can not call the police" clear boundary.

1. look at the law first: what public security manages, no matter what

Public security organs are under the jurisdiction of public security violations and criminal crimes. Extramarital affairs, adultery and cohabitation are not public security violations, nor are they crimes, so they do not belong to the scope of alarm treatment. Article 78 of the Public Security Administration punishment Law (revised on June 27, 2025 and implemented on January 1, 2026) stipulates that those who engage in prostitution or whoring shall be detained for not less than 10 days but not more than 15 days, and may also be fined not more than 5000 yuan; if the circumstances are relatively minor, they shall be detained for not more than five days or fined not more than 1000 yuan; those who solicit prostitutes in public places shall be detained for not more than five days or fined not less than 1000 yuan. Attention should be paid to two points: first, the current provisions have been adjusted from the old version of article 66 to article 78 (the expression quoted in article 66 in the old law era is outdated); Second, the punishment object is "prostitution and whoring"-if the husband and a third party are paid sex transactions, which are prostitution, the police can investigate and deal with them after calling the police, and the spouse can also obtain the administrative punishment record of the public security organ as evidence of divorce fault.

Article 238 of the Criminal Law stipulates the crime of bigamy: those who have a spouse and bigamy, or those who know that others have a spouse and marry them, shall be sentenced to fixed-term imprisonment of not more than two years or criminal detention. The crime of bigamy can be prosecuted by the victim to the people's court or reported to the public security organ; those who "live together in the name of husband and wife" or register marriage outside marriage are suspected of bigamy, which can be reported to the police. In addition, if derailment is accompanied by domestic violence, illegal detention (such as restricting the other party's personal freedom "custody"), rape, etc., of course, you can call the police.

also need to specifically explain the distinction of "paid housing": heterosexual housing outside marriage is voluntary, no money transactions, adultery rather than prostitution, which does not constitute a public security violation; in practice, the police usually register the "catch rape" alarm as a dispute or not accept it, and the "police break the door to catch rape" expected by the parties has no legal basis, the police also have no such authority-breaking into a hotel room may in turn be illegal.

needs to supplement the change of punishment caliber: the revised Public Security Administration Punishment Law in 2025 will adjust the provisions of prostitution and whoring from Article 66 of the old version to Article 78, and will be implemented from January 1, 2026, and the upper limit of fine for "minor circumstances" will be adjusted from 500 yuan to 1,000 yuan, under normal circumstances, they are still detained for not less than 10 days and not more than 15 days, and may also be fined not more than 5,000 yuan-after the implementation of the new law, the law enforcement basis shall be subject to the current article number, and the old materials citing the old article number are no longer accurate. For spouses, the record of being punished for whoring is not only evidence of fault, but also may affect their image evaluation as parents, and become a disadvantageous factor in the struggle for custody -- the legal record of administrative punishment is sometimes more important than the "iron evidence" secretly photographed by private people, which is the value of "going the right way to the police.

Three Cases of 2. Alarm and Police Handling Methods

Case 1: Suspected of prostitution. If you have any evidence or leads—such as the other party entering a hotel with individuals engaged in paid sexual transactions, or online advertisements for prostitution—you may call 110 or report the matter to the local police station. The police will investigate in accordance with the law and, upon verification, impose administrative penalties on those involved in prostitution or soliciting prostitution. Note: False reporting of "prostitution and whoring" based on suspicion alone may constitute a false report of police information and a waste of police force. If the circumstances are serious, it is suspected of breaking the law. Do not fabricate facts.

Scenario 2: Suspected bigamy. If a spouse registers marriage with a third party or cohabits with them under the guise of a marital relationship, one may file a report with the public security authorities or directly bring a criminal private prosecution before the People’s Court. The threshold for determining the crime of bigamy is relatively high, which requires evidence of "having a spouse and marrying others or living together in the name of husband and wife" (public cohabitation, matching husband and wife, giving birth to children together, etc.), and opening a house at one time is far from the standard.

Case 3: Only suspected cheating to open a room. The police generally do not deal with it and will inform it to resolve it through negotiation and litigation. At this time, the main significance of calling the police is limited-if the police are called and recorded, the time and place of the police can be used as auxiliary evidence for clues of whereabouts, but cannot replace legal evidence collection. Do not expect the police to produce a "derailment certificate", the police do not have the authority to do so.

Alternative Path to 3. Forensics: What Can Legal Means Get

The alarm does not work, and evidence collection depends on legal means:

  1. self-admission documents of the other party: guarantee, repentance and commitment, which clearly state the facts and objects of the house opening, and have the highest probative force (pay attention to the peaceful writing process and avoid coercion);
  2. Electronic evidence: WeChat chat records (keeping the original carrier, recording the screen and notarizing if necessary), transfer records (520/1314 and other special amounts), reservation orders and payment records;
  3. Images in public places: intimate images taken in public places (shopping malls, streets, communities) can be used as evidence;
  4. litigation investigation order: after the lawsuit, apply to the court for investigation and evidence collection or investigation order, and obtain the materials that cannot be obtained by individuals, such as hotel check-in registration, bank flow, call details, etc;
  5. administrative punishment record: if the police have punished the other party because of prostitution and whoring, the punishment decision is a strong documentary evidence;
  6. Witness Testimony: The insider testifies in court.

On the whole, we should grasp a principle: those that can be legally obtained by ourselves (self-owned equipment, self-owned accounts, public places, self-admission of the other party), those that need the support of other people's data should go through the court investigation order, and the "internal information" with unknown sources should not be used-the legality of the evidence is not enough, no matter how much it is, it is also negative equity, and even drag down the credibility of the whole group of evidence.

The red line of evidence collection reiterates: do not intrude into hotel rooms, do not invade other people's houses, do not follow and secretly take pictures, and do not spread the privacy of the other party publicly -- the violator may become the defendant of infringement disputes from "victim", and the illegally obtained evidence may also be excluded in court.

After the 4. evidence is obtained: How to connect the divorce rights

The legal evidence should finally serve the claims of divorce: firstly, to prove the emotional breakdown and pave the way for the first divorce lawsuit; secondly, to claim compensation for divorce damages-the legal situations stipulated in Article 1091 of the Civil Code are bigamy, cohabitation with others, domestic violence, abuse and abandonment of family members, etc. Occasionally opening a house may not fall into "cohabitation with others", however, serious faults can be fought according to the "other major faults" clause and the principle of fault liability. Ningbo also has local cases of compensation in the case of bigamy. Third, it is claimed that the property is divided less or the gift is recovered-according to Article 7 of the (II) of Interpretation, if the common property is given to a third party for the purpose of violating the duty of loyalty such as bigamy or cohabitation with others, it can be claimed that the gift is invalid and returned. Fourth, competition for custody-if one party has serious faults such as bigamy or cohabitation with another person, it will affect the qualification for direct custody (Article 14 of the Interpretation (II)). The proof strength of the evidence determines the fineness of the claim: a record of opening a house can prove "deviant", the evidence of continuous cohabitation can support the high-intensity claim, and the direction of evidence collection should match the litigation target.

In practice, evidence of “cohabiting as husband and wife” commonly includes: chat records in which the two parties refer to each other as husband and wife, as well as witness testimony from relevant occasions; joint attendance at gatherings with relatives and friends in the capacity of spouses; long-term cohabitation and joint upbringing of children; records of a marital relationship in household registration or other official documents; and entries in the birth certificate of a child indicating the father’s identity. It should be noted that the crime of bigamy requires "having a spouse and marrying others or living together in the name of husband and wife", which is essentially different from simple cohabitation outside marriage; even if it does not constitute bigamy, continuous and stable cohabitation is still the cause of damages for "cohabitation with others" in Article 1091 of the Civil Code. If the spouse and the third party have children, the relevant kinship facts prove that not only strengthen the fault determination, but also affect the calculation of alimony and compensation-such evidence can be obtained in accordance with the law through paternity testing procedures, do not "rob the child" type of evidence or compulsory blood collection, so as not to intensify civil disputes into public security issues.

The evidentiary value of 5. administrative and criminal records: the correct "opening method" of the alarm"

Although the alarm itself cannot "catch the traitor", it can be exchanged for an official document with great probative force under certain circumstances, which many people ignore:

  1. Administrative Penalty Decision: If a husband is penalized by the public security authorities for soliciting prostitution, the penalty decision constitutes an official document that records the time, place, and facts of the violation, and thus carries significant evidentiary weight in divorce proceedings—it effectively serves as the public security authorities’ evidence of infidelity on your behalf and cannot be easily rebutted. This is also the most valuable scene of "calling the police": if there is evidence to suspect prostitution, the police are not to catch the rape on the spot, but to get an official record of the violation.
  2. Criminal filing and adjudication documents: If the bigamy crime is filed for investigation, prosecution and judgment, the relevant legal documents directly lock in the fact that "living together in the name of husband and wife", which is the ironclad evidence of damage compensation and fault determination; in the local case of Ningbo, the guilty party of bigamy and having children is judged to pay economic compensation and damage compensation, which is based on the fact of criminal or administrative determination.
  3. police record: after the general family dispute is reported to the police, the police record can prove that there have been conflicts or abnormal situations at a specific time and place, which can be used as the auxiliary evidence of whereabouts clues, but can not prove "derailment" itself.
  4. Domestic violence warning letter and injury identification: if derailment is accompanied by domestic violence, the warning letter and injury examination record obtained after calling the police are the key materials for claiming damage compensation and fighting for custody.

The reverse side of the warning is equally important: reporting a crime to the police with the intent of extracting a confession, fabricating evidence of prostitution to make a false report, or using police dispatch as a means of pressuring the other party may result in administrative penalties for making a false alarm. Moreover, any “evidence” obtained through such unlawful means will be deemed inadmissible in legal proceedings. The correct way to report a crime is: “If there is illegal or criminal activity, first report it and obtain official documentation; if there is no illegal or criminal activity, gather evidence legally and pursue legal action.” The clearer you keep these two paths separate, the smoother your rights‑protection process will be.

6. FAQ

If you call the police to a hotel to “catch someone in the act,” will they respond?

Usually not. Adultery and extramarital affairs are not public security violations or crimes, and the police do not have the power to "catch adultery"; it is only meaningful to call the police when prostitution, bigamy, violence and other crimes are involved. Breaking into a hotel room for evidence may be illegal.

If my husband rents a hotel room for prostitution, what can I get after calling the police?

The police will impose administrative penalties on the prostitutes after verification, and the penalty decision can be used as evidence of fault in divorce proceedings; when calling the police, state the clues truthfully and don't make up the plot of "prostitution.

Under what circumstances can one report bigamy to the police?

If a spouse has registered marriage with another person, or has not registered but continues to live together in the name of husband and wife, and is recognized by the surrounding people, and is suspected of the crime of bigamy, he may report the case to the public security organ or file a private prosecution with the court. An open house, a brief cohabitation usually does not constitute bigamy.

Can the alarm record be used as evidence?

The receipt of the alarm and the record of the alarm can be used as the auxiliary evidence of the clues of time and place (to prove that there is a dispute in a certain place at a certain time), but the police do not make the determination of "whether derailment or not"; the core fault fact still depends on the proof of chat records, transfer, hotel records, self-identification documents and so on.

If I have been penalized by the public security authorities for prostitution or soliciting, can this be used as evidence in a divorce proceeding?

Yes, and it carries strong probative force. An administrative penalty decision is an official documentary evidence that records the time, place, and facts of the violation. In divorce litigation, it may be submitted directly as evidence of fault without the need to separately prove “whether adultery occurred.” If the other party denies the allegations, you may apply to the court to obtain the penalty file from the public security authorities. This is also the most valuable use of "calling the police"-not to catch the rape on the spot, but in exchange for an official record of the violation.

7. Practical insights from a lawyer

Before calling the police, first clarify what the public security authorities handle and what they don’t; otherwise, you might make a wasted trip and even run into trouble. Ordinary extramarital affairs and hotel check-ins do not, in themselves, constitute public security or criminal offenses; the police generally will not initiate a case based solely on such incidents, nor will they “arrest people and gather evidence” on your behalf. However, if the situation involves bigamy, fraud, unlawful intrusion, invasion of privacy, or if illegal acts occur during a conflict, the police may intervene. Therefore, before calling the police, first determine whether your concern is about evidence collection or public order. The objectives are different, and the approaches should be entirely distinct—do not conflate the two.

The alternative path of forensics must be legal. Installing a GPS tracker on your own, secretly filming someone’s private spaces, or illegally accessing another person’s communication records can easily turn what you perceive as justified into an illegal act, and any evidence obtained in this way may not be admissible in court. A more stable approach is to build around materials that can be obtained legally: written assurances or acknowledgements from the other party, records of chats and transfers between the parties, records of joint trips in public, and daily traces that reflect the continuity of the relationship. Focus on whether the relationship is consistently stable, rather than on sensational details.

After getting the evidence, it should be connected with divorce rights protection: these materials are more used to prove fault, support damage compensation and the tendency in division and upbringing, instead of relying on a single record of opening a room to decide who can't leave and who the children belong. During negotiations, you can use the facts of the wrongdoing as leverage, but avoid revealing your entire hand too early.If you do encounter situations involving public security or criminal matters, you should formally report the case and keep the records of the case and the police. You should pay attention to legality and restraint in the whole process. Don't let yourself step on the line first, otherwise it will become difficult to tell the truth.

"Catch a traitor by calling the police" is a false proposition in most cases-the police just violate the law and commit crimes regardless of moral problems. The rational approach is three steps: the first step is to judge whether there is any illegal crime (whoring, bigamy, violence), and some call the police and save the handling documents; The second step is to legally obtain evidence, build a chain of evidence with self-confessed documents, electronic data, public images and investigation orders, and never cross the border to secretly take photos and rush into it. The third step is to turn the evidence into divorce claims-emotional breakdown, damages, property tilt, recovery, each shall be prepared according to the respective certification standards. If you think clearly about "what the police are for", you will find that legal evidence collection and litigation are the really useful weapons. In Ningbo, the mechanisms of pre-litigation mediation, property declaration and investigation order in family trials are quite mature enough to support this path-handing over emotions to legal procedures and evidence to the court, and the results are often much fairer than acting on impulse.