(1) Technical investigation methods

Technical investigation methods refer to the use of professional investigators in order to obtain various intelligence, information, materials, etc. about criminal cases in the investigation of various criminal cases. Know-how, methods, means and measures secretly adopted by personnel through special procedures and in accordance with the law.

(2) Criminal technical investigation methods

Using technical investigation methods to discover and expose crimes is a common practice for investigative agencies around the world to fight crime.

(3) Technical investigation measures

Technical investigation measures refer to a specific method adopted by the investigative agency after strict review and approval in accordance with relevant national regulations in order to detect specific criminal acts. technical means. Technical investigation behavior is the investigation behavior that uses technical investigation measures. It usually includes secret specialized technical means such as electronic interception, telephone monitoring, electronic surveillance, secret photography, video recording, and mail checking.

Criminal investigation coercive measures

1 Interrogation of criminal suspects

Interrogation of criminal suspects refers to investigators questioning criminal suspects verbally in accordance with legal procedures An investigative act based on the facts of the case and other circumstances related to the case.

Procedures and methods for interrogating criminal suspects

1. Subject of interrogation

Interrogation of criminal suspects must be conducted by investigators from the public security organ or the People’s Procuratorate . In order to improve the efficiency of interrogation, ensure the quality of interrogation, prevent violations of laws and disciplines, and ensure the safety of interrogation, there should be no less than 2 investigators during interrogation.

2. Place of interrogation

(1) After the criminal suspect is sent to the detention center for custody, investigators shall interrogate him in the detention center.

(2) For criminal suspects who do not need to be arrested or detained, they can be summoned to a designated place in the city or county where the criminal suspect is located or to his residence for interrogation, but the public security organ or people's certificate must be produced Prosecution documents from the Procuratorate.

3. Time for interrogation

(1) The maximum duration of summons or subpoena shall not exceed 12 hours; if the case is serious and complex and requires detention or arrest measures, summons, The detention period shall not exceed 24 hours. Article 195 of the "High Procuratorate Rules" stipulates that the time between two summonses shall generally not be less than 12 hours.

(2) Criminal suspects shall not be detained in disguised form in the form of consecutive summons or custodial summons.

(3) Criminal suspects who have been detained or arrested must be interrogated within 24 hours after being detained or arrested. When it is found that they should not be detained or arrested, they must be released immediately.

4. Interrogation steps and methods

(1) When interrogating a criminal suspect, investigators should first ask the criminal suspect whether he has committed a crime.

(2) If the criminal suspect admits to committing a crime, ask him to state the circumstances of his guilt; if the criminal suspect denies the crime, ask him to state his defense of innocence, and then based on his statement, Ask the suspect questions.

(3) Criminal suspects should answer truthfully the questions raised by investigators. However, they have the right to refuse to answer questions that are irrelevant to this case.

(4) Interrogation transcripts shall be produced when interrogating criminal suspects. The transcript should truthfully record the questions, answers and other people present.

(5) When interrogating criminal suspects, it is strictly prohibited to use torture to extract confessions, nor to induce, deceive, or name confessions. Criminal suspects have the right to file charges against those who use torture to extract confessions; if a crime is constituted, they shall be held criminally responsible in accordance with the law.

5. Interrogation of special criminal suspects

When interrogating deaf or mute criminal suspects, people who are familiar with deaf or mute gestures should participate, and this situation should be recorded record. When interrogating a minor criminal suspect, his or her legal representative may be notified to be present. If the criminal suspect is not proficient in the local language, he or she should be translated.

2 Questioning witnesses and victims

Interrogating witnesses refers to an investigative behavior in which investigators use words to investigate and understand the case situation from witnesses in accordance with legal procedures.

Procedures for questioning witnesses:

1. Witness questioning can only be conducted by investigators. The number of investigators shall not be less than two.

2. When investigators interrogate witnesses, they can go to the witness’s unit or residence, but they must produce certification documents from the public security agency or the People’s Procuratorate.

3. Witnesses should be questioned individually.

4. In order to ensure that the witness truthfully provides evidence, when interrogating the witness, he should be informed that he must truthfully provide evidence and testimony and the legal liability for intentional perjury or concealment of criminal evidence.

5. When questioning witnesses under the age of 18, their legal representatives may be notified to be present.

6. When questioning a witness, generally the witness should first be asked to give a continuous detailed description of the situation he knows, and ask about the source of the facts described, and then combine the facts and facts that should be determined in the case based on his description. Ask the witness questions about the circumstances and let the witness answer them.

7. A transcript of the witness’s narrative should be made and submitted to the witness for verification or read to him.

3 Inspection and inspection

Inspection and inspection, including inspection and inspection. The objects of the inspection are the scene, objects and corpses, while the object of the inspection is the person. The inspection includes on-site inspection, physical evidence inspection and corpse inspection.

1. On-site inspection procedures

(1) Protect the site. All units and individuals have the obligation to protect the crime scene and immediately notify the public security organs to send personnel to investigate. After receiving the case, investigators should rush to the crime scene quickly and protect the scene.

(2) When conducting on-site inspections, investigators must hold certification documents from the public security agency or procuratorate.

(3) When necessary, persons with specialized knowledge may be assigned or hired to conduct an inspection under the auspices of investigators. Two witnesses not connected with the case should also be invited to be present.

(4) When conducting on-site inspections, investigators should promptly investigate and interview the people around the scene, victims, witnesses, reporters, etc., and collect, fix and preserve various evidences.

(5) The on-site inspection shall be recorded in a written record, and investigators, other persons participating in the inspection and witnesses shall sign or seal the record.

2. Procedures for physical evidence inspection

(1) The physical evidence must be inspected promptly, carefully and meticulously. If specialized technical personnel are required for inspection and identification, they should be assigned Or hire an appraiser to conduct an appraisal.

(2) A transcript shall be made for the examination of physical evidence, and all investigators, appraisers and witnesses participating in the examination shall sign or seal it.

3. Autopsy procedures

(1) For corpses whose cause of death is unknown, with the approval of the person in charge of the public security organ at or above the county level, the corpse can be dissected or the coffin opened for examination, and the deceased can be notified Family members were present.

(2) Regarding the autopsy, a transcript shall be made and signed or sealed by the investigators, forensic examiner or physician.

4. Personal examination procedures

(1) Personal examination of victims and criminal suspects must be conducted by investigators. When necessary, forensic scientists or doctors may be hired under the auspices of investigators to conduct the investigation strictly in accordance with the law and shall not insult the personality of the person being examined.

(2) Physical examination of criminal suspects may be conducted by force if necessary. However, the physical examination of the victim shall not be compulsory. Examination of women's bodies should be carried out by female staff or doctors.

(3) A record of the personal examination shall be made and signed or sealed by the investigators and the forensic examiner or physician who conducted the examination.

4 Search

Search is when judicial organs collect criminal evidence, seize criminals, and search the bodies, belongings, residences and other relevant objects of defendants and people who may hide criminals or criminal evidence in accordance with the law. Compulsory method of searching and inspecting places.

Search procedures:

1. Searches can only be conducted by investigators of public security organs, people’s procuratorates and other investigative agencies in accordance with the law. No other agency, group or individual has the right to search the person of a citizen. and residences were searched.

2. During the search, there must be more than two investigators and a search warrant issued by the main person in charge of the investigation agency at or above the county level.

3. All units and individuals are obliged to hand over physical evidence, documentary evidence, and audio-visual materials that can prove the guilt or innocence of the criminal suspect in accordance with the requirements of the public security organs and the People's Procuratorate. Otherwise, the investigation agency can force the extraction according to law.

4. During the search, the person being searched or his family members, neighbors or other witnesses should be present.

5. Women’s body searches should be conducted by female staff.

6. The search shall be recorded in a written record, signed or sealed by the investigators and the person being searched or his family members, neighbors or other witnesses. If the person being searched is at large or his family members refuse to sign or seal, this shall be recorded in the transcript.

Seizure of physical evidence and documentary evidence

Seizure of physical evidence and documentary evidence refers to an investigative act in which the investigative agency compulsorily detains or freezes items, documents, and money related to the case in accordance with the law.

Procedures for seizing physical evidence and documentary evidence:

1. Enumeration. Investigators shall work with witnesses present and the holders of the seized or seized property and documents to conduct an inspection. The property and documents should be clearly counted;

2. Make a list. Based on the count, a list should be made on the spot in duplicate, and the names, specifications, and Characteristics, quality, quantity, document number, as well as the location where the property and documents were found, the time of sealing and detaining, etc.;

3. Signed and sealed, the list should be signed by the investigators, the holder and the person present The signature or seal of the witness;

4. Keep, one copy of the list of seals and seizures shall be given to the holder or his family, and the other shall be filed by the investigative agency for reference. The list drawn up on the spot cannot be altered. If any correction is necessary, it must be signed or stamped by the investigators, the holder and the witness, or the list must be re-drawn.

6 Identification

Identification means that in order to find out the facts of the case during the investigation, when necessary, let the victims, witnesses and criminal suspects identify items, documents, bodies, places or objects related to the crime. An investigative act to identify criminal suspects.

Procedures for identification:

1. If the public security organs and people’s procuratorates need to identify criminal suspects during the investigation of cases under their respective jurisdictions, they shall consult the person in charge of the case-handling department or the procuratorate respectively. Chief approves.

2. The identification should be conducted under the supervision of investigators.

3. When multiple identifiers identify the same identification object, each identifier shall conduct the identification independently. Witnesses may be present if necessary.

4. When identifying, the object of identification should be mixed with other people or objects, and no hint should be given to the person identifying.

5. In cases investigated by public security organs, if the identification person is unwilling to conduct the identification in public, the identification can be conducted without exposing the identification person, and the investigators shall keep it confidential.

6. Regarding the identification, a transcript should be made and signed or sealed by the investigators, identifiers and witnesses who presided over and participated in the identification.

7 Wanted

Wanted refers to an investigative act in which the public security organ or the People's Procuratorate issues a warrant to apprehend a fugitive criminal suspect who should be arrested and brought to justice.

Wanted procedures:

1. Only the public security organs have the right to issue wanted orders, and no other agencies, groups, units, organizations or individuals have the right to issue them. When the People's Procuratorate needs to pursue a fugitive criminal suspect in a self-investigation case, it shall, with the approval of the Chief Prosecutor, make a wanted decision and notify the public security organ, who will issue a wanted order.

2. Public security organs at all levels are within the areas under their jurisdiction.

3. The wanted objects must be criminal suspects who should be arrested according to law but are at large, including criminal suspects who have been arrested but escaped while in custody.

4. The wanted person’s name, alias, previous name, nickname, gender, age, ethnicity, place of origin, place of birth, place of household registration, place of residence, occupation, and ID card should be stated in the wanted order. The number, clothing and physical characteristics should be accompanied by a photo of the wanted person, and photos of fingerprints and other physical evidence can be attached. In addition to matters that must be kept confidential, the time, place and brief facts of the case should be stated.

5. After a wanted order is issued, a new notice can be issued if new important circumstances are discovered. The notification must indicate the number and date of the original wanted order.

6. After receiving the wanted order, the relevant public security organs should promptly arrange for the arrest. After a criminal suspect is captured, the arrest warrant issuing authority shall be promptly notified, and the suspect shall be detained on the basis of the arrest warrant after approval by the person in charge of the public security organ at or above the county level in the place where the suspect was captured. The original arrest warrant issuing authority should immediately verify the case and handle it in accordance with the law.

7. If the wanted person has been brought to justice or died, or the reason for the wanted has disappeared and there is no need for the wanted, the agency that issued the wanted order shall immediately notify the cancellation of the wanted order within the scope of the original issuance.

Legal Basis

"Criminal Procedure Law of the People's Republic of China"

Article 52 Judges, prosecutors and investigators must comply with Legal procedures to collect various evidence that can prove the guilt or innocence of criminal suspects and defendants and the seriousness of the crime. It is strictly prohibited to use torture to extract confessions and to collect evidence through threats, inducements, deceptions and other illegal methods, and no one may be forced to prove his or her guilt. It must be ensured that all citizens who are related to the case or know the facts of the case have the conditions to objectively and fully provide evidence. Except for special circumstances, they can be recruited to assist in the investigation.