How Far Must a Military Prosecutor's Seizure Relate to the Case? Nexus, the Suspect's Right of Participation and the Exclusion of Illegally Obtained Evidence under the Military Court Act

Question

Offences committed by soldiers and military civilian employees are often investigated and tried under the procedures laid down in the Military Court Act. The Military Court Act is a statute separate from the Criminal Procedure Act, but its provisions on seizure, search and evidence follow an almost identical structure. Article 359-2 of the Military Court Act uses the same wording as Article 308-2 of the Criminal Procedure Act and provides that evidence collected without following due process shall not be admissible as evidence. The first question, then, is whether the doctrines on nexus and the right of participation developed in ordinary criminal procedure carry over unchanged to military court proceedings.

Judgment 2021Do8284 addressed whether a seizure and search carried out by a military prosecutor in the course of an investigation governed by the former Military Court Act is subject to the nexus requirement and, if so, how far that requirement extends. At the time, the provision empowering military prosecutors to seize and search contained no wording that expressly imposed a nexus requirement, and the Supreme Court derived the requirement through the provisions applied mutatis mutandis. Judgment 2020Do1669 addressed the suspect's right of participation where a third party, such as the victim, voluntarily produced the suspect's information storage medium; derivative evidence obtained on the basis of illegally collected evidence; and the inadvertent discovery of electronic information relating to a separate offence. Its summary of judgment cites both Article 308-2 of the Criminal Procedure Act and Article 359-2 of the Military Court Act.

This brief divides the inquiry into four questions. First, what it means for an item to be related to the case in a military prosecutor's seizure and search, and how far objective and personal nexus extend. Second, how to read a seizure made under the former Act, which contained no nexus wording. Third, when the right of participation must also be guaranteed to the suspect where a third party has voluntarily produced an information storage medium. Fourth, how to treat derivative evidence obtained from primary evidence collected in breach of procedure, and information relating to a separate offence discovered inadvertently.

This brief sets out the strands of doctrine only within the scope of what the summaries of holdings and summaries of judgment of the two Supreme Court judgments state. It does not assess the admissibility of evidence in any particular case. Because provisions of both the Military Court Act and the Criminal Procedure Act have been amended since the judgments, each judgment is read against the legislation in force at the time of the conduct, and differences from the current wording are noted.

Material to check

First, the current wording of Article 254 of the Military Court Act and how it differs from the former Act. Article 254(1) of the former Military Court Act (before its amendment on 9 June 2020), as cited in Judgment 2021Do8284, provided that a military prosecutor may, where necessary for a criminal investigation, conduct a seizure, search or inspection under a warrant issued, upon the military prosecutor's request, by a military judge of the competent ordinary military court. Following amendments on 6 January 2016, 9 June 2020 and 24 September 2021, the current Article 254(1) provides that a military prosecutor may, where necessary for a criminal investigation, conduct a seizure, search or inspection under a warrant issued by a military judge of the competent military court, limited to cases where there are circumstances giving reason to suspect that the suspect has committed an offence and to items that can be recognised as related to the case in question. Paragraph (2) requires a military judicial police officer to apply to a military prosecutor and to act under a seizure and search warrant issued upon the military prosecutor's request.

Second, the provisions applied mutatis mutandis. Current Article 258 of the Military Court Act provides that, where a military prosecutor or military judicial police officer conducts a seizure, search or inspection, Articles 146, 147, 149 to 152, 154, the main text of Article 156(1), paragraphs (2) and (3) of the same Article, Articles 159 to 173, 175, 176, 181, 182, 390(2) and 528 apply mutatis mutandis. Article 146(1) provides that the military court may, where necessary, seize evidence or articles considered to be subject to confiscation, limited to items that can be recognised as related to the case against the defendant; Article 149(1) provides that, subject to the same limitation, the court may search the defendant's body, articles, residence or other places. Article 146(3) provides that, in the case of information storage media, etc., the principle is to have the stored information produced by printing out or copying it within a specified scope.

Third, the provisions on participation and inventories. Article 162 of the Military Court Act provides that the military prosecutor, the defendant or defence counsel may participate in the execution of a seizure and search warrant, and Article 163 requires the date, time and place of execution to be notified in advance to the persons specified in Article 162, except where they have expressed an intention not to participate or in cases of urgency. Article 170 requires that, where items are seized, an inventory be prepared and delivered to the owner, possessor, custodian or any other person equivalent thereto. Article 257 provides that a military prosecutor or military judicial police officer may seize without a warrant articles left behind or articles voluntarily produced by their owner, possessor or custodian. The corresponding provisions of the Criminal Procedure Act are Article 121 (execution of warrants and participation of parties), Article 129 (delivery of the inventory of seized items) and Article 218 (seizure without a warrant).

Fourth, the amendments on the Criminal Procedure Act side. Under the amendment of 4 August 2026, paragraph (1) of current Article 215 of the Criminal Procedure Act was deleted, leaving only the seizure by a judicial police officer under a warrant in paragraph (2), and Articles 218 and 219 were wholly amended on the same date so as to name the judicial police officer as the actor. Article 106(1) provides that the court may, where necessary, seize items, limited to those that can be recognised as related to the case against the defendant, and paragraph (3) sets out the principle of printing out or copying information storage media, etc. within a specified scope. By contrast, Article 254 of the Military Court Act retains the military prosecutor's power to seize under a warrant, so the correspondence between the provisions of the two Acts is no longer the same after the 2026 amendment as it was before. Articles 218 and 219 of the Criminal Procedure Act, cited as reference provisions in Judgment 2020Do1669, were wholly amended after the judgment, so their wording at the time of the judgment must be checked separately.

Fifth, the provisions on jurisdiction and transfer. Current Article 2(2) of the Military Court Act, as amended on 24 September 2021, gives the ordinary courts jurisdiction over sexual crimes under Article 2 of the Act on Special Cases concerning the Punishment of Sexual Crimes and offences under Article 15-2 of the same Act, among others, over crimes that caused death, and over crimes committed before acquiring the relevant status, where committed by persons specified in Article 1(1) to (3) of the Military Criminal Act, except in time of war, incident or a national emergency equivalent thereto. Paragraph (3) provides that, where it becomes clear that a military court has ceased to have, or never had, jurisdiction over a case in which a public prosecution has been instituted, the case shall be transferred to a court of the same instance having jurisdiction, and procedural acts performed before the transfer remain effective. The operative part of Judgment 2020Do1669 states that the part of the judgment below convicting the defendant is reversed and transferred to the Seoul High Court; the basis for that transfer is a matter to be checked in the full text of the judgment.

Sixth, Articles 243 and 244 of the Criminal Act. Article 243 punishes a person who distributes, sells or rents, or publicly displays or screens, obscene documents, drawings, films or other articles, and Article 244 punishes a person who manufactures, possesses, imports or exports obscene articles for the purpose of the acts under Article 243. Alongside the admissibility issues, Judgment 2020Do1669 decided whether a computer program file constitutes an article under these provisions.

Possible readings

The first divergence concerns how to fill the gap in the wording of the former Act. One reading notes that Article 254(1) of the former Military Court Act imposed only the requirement that the measure be necessary for a criminal investigation, which leaves room for the view that a military prosecutor's investigative seizure and search need satisfy only necessity, on the premise that a warrant has been issued. The other reading holds that, because Article 258 applies mutatis mutandis Articles 146(1) and 149(1) on seizure and search by the military court, the limitation in those provisions, 'limited to items that can be recognised as related to the case against the defendant', also extends to a military prosecutor's seizure and search. Judgment 2021Do8284 adopted the latter reading.

The second divergence concerns the breadth of objective nexus. A narrow reading confines it to cases directly related to the suspected facts stated in the warrant themselves or to offences sharing the same basic facts. A broad reading extends it to cases where the item may serve as indirect or circumstantial evidence proving the motive and background of the offence, its means and method, or its time and place, or as corroborating evidence for a confession. Judgment 2021Do8284 accepted the broad reading but drew a limit: there must be a specific and individual connection, and objective nexus cannot be recognised merely on the ground that an offence is of the same kind as, or similar to, the suspected facts.

The third divergence concerns the scope of personal nexus. One reading confines it to the person named in the warrant; another extends it to accomplices, indirect principals and necessary accomplices. Judgment 2021Do8284 held that personal nexus may be recognised not only for cases against accomplices of the person named in the warrant, such as co-principals or instigators, or indirect principals, but also for cases against necessary accomplices and the like.

The fourth divergence concerns the suspect's position where a third party voluntarily produces an item. One reading holds that the person who voluntarily produced the item is the person from whom the items were seized, so the right of participation need be guaranteed to that person only. The other reading holds that, if the information storage medium belongs to the suspect's ownership or control, the suspect is the person from whom the items were substantively seized, so procedural rights such as the right of participation and the delivery of an inventory of electronic information must also be guaranteed to the suspect. Judgment 2020Do1669 adopted the latter reading and based the test not on a legal, ex post assessment according to the attribution of rights under civil law, but on the de facto state of affairs that was outwardly and objectively recognisable at the time of the seizure and search.

The fifth divergence concerns the consequences of a procedural breach. One reading uniformly excludes derivative evidence obtained on the basis of illegally collected primary evidence; another admits an exception, after examining the individual circumstances, where the causal link has been attenuated or severed. Judgment 2020Do1669 held that derivative evidence likewise cannot, in principle, be used as evidence for a finding of guilt, and directed that all circumstances relating to the collection of the primary evidence and the circumstances arising additionally in the course of collecting the derivative evidence be considered as a whole and comprehensively, focusing on whether the causal link has been attenuated or severed. Where information relating to a separate offence is discovered inadvertently, it held that further searching must cease and a separate warrant must be obtained.

Read together, the two judgments indicate that the evidentiary doctrines of military court proceedings and ordinary criminal procedure are converging on the same standards. However, the provisions of the two Acts have been amended at different times, and since the 2026 amendment of the Criminal Procedure Act the correspondence regarding investigating authorities has changed. Through which provision the same standard applies is left for the reader to determine after checking the legislation in force at the time of the conduct.

What the decisions held

Supreme Court Judgment 2021Do8284 rendered on 27 February 2025 addressed the admissibility of documents seized by a military prosecutor executing a seizure and search warrant in a case concerning a violation of the Military Secret Protection Act. Referring to Articles 146(1) and 149(1), which apply mutatis mutandis to a military prosecutor's investigative seizure and search under Article 258 of the former Military Court Act, the judgment stated that "an investigative seizure and search by a military prosecutor to which the former Military Court Act applies is likewise subject to the nexus requirement," and that being related to the case "means that the item is related to the suspected facts stated in the seizure and search warrant, has at least the minimum value of being capable of proving them, and has an objective and personal nexus with the suspected facts in the seizure and search warrant." Objective nexus may be recognised not only where the item is directly related to the suspected facts themselves or to an offence sharing the same basic facts, but also where it may be used as indirect or circumstantial evidence or as corroborating evidence for a confession; however, the judgment held that "objective nexus cannot be found merely on the ground that an offence is of the same kind as, or similar to, the suspected facts." The operative part reads: the judgment below is reversed, and the case is remanded to the Suwon District Court.

Supreme Court Judgment 2020Do1669 rendered on 14 December 2023 first held, with respect to Article 243 of the Criminal Act, that "a computer program file cannot be regarded as falling under the documents, drawings, films or other articles provided for in the above provision," and that this applies equally to the interpretation of 'obscene articles' in Article 244 of the Criminal Act. It went on to hold that, where a third party such as the victim voluntarily produces an information storage medium belonging to the suspect's ownership or control, appropriate measures must, absent special circumstances, be taken to guarantee the suspect's procedural rights, such as guaranteeing the right of participation and delivering an inventory of the seized electronic information. It summarised an information storage medium belonging to the suspect's ownership or control as one that the suspect, at the time of the seizure and search or up to a time closely proximate to it, actually controlled and managed while holding and exercising exclusive rights of management and disposal over the electronic information in it as a whole, without having transferred or waived those rights to a third party. Whether that is so, it held, "must be determined on the basis of the de facto state of affairs that was outwardly and objectively recognisable at the time of the seizure and search."

Citing Article 308-2 of the Criminal Procedure Act (Article 359-2 of the Military Court Act), the same judgment held that not only evidence collected by investigative agencies without following the procedures prescribed by the Constitution and the Criminal Procedure Act, but also "derivative evidence obtained on the basis thereof likewise cannot, in principle, be used as evidence for a finding of guilt." It directed that the admissibility of derivative evidence be determined by considering as a whole and comprehensively, focusing on whether the causal link has been attenuated or severed, the purpose of the procedural provision, the nature and degree of the breach, the circumstances of the breach and its avoidability, the nature of the protected legal interest and the degree of its infringement, the causal link, and the awareness and intent of the investigative agency, together with the circumstances arising additionally in the course of collecting the derivative evidence. It held that, in respect of a voluntarily produced information storage medium, searching, copying or printing out electronic information at the investigative agency's discretion beyond the scope of the items to be seized is, in principle, unlawful, and that where information relating to a separate suspected offence is discovered inadvertently while lawfully searching for electronic information related to the facts constituting the suspected offence, "the investigative agency must cease any further searching and may lawfully seize and search such information only where it has obtained from the court a seizure and search warrant for the separate suspected offence." The operative part reversed the part of the judgment below convicting the defendant and transferred that part of the case to the Seoul High Court.

Practical checklist

This section is not advice; it is a set of questions that may be asked when checking the record. First, the applicable legislation may be queried. It may be checked first when and by whom the seizure and search was executed, what the wording of Articles 254 and 258 of the Military Court Act and the corresponding provisions of the Criminal Procedure Act was at that time, and whether the case was pending before a military court or an ordinary court.

Second, nexus may be queried. The seized documents or electronic information may be sorted item by item according to what specific and individual connection they have with the suspected facts stated in the warrant: whether they are evidence of the suspected facts themselves, indirect or circumstantial evidence proving motive, background, means, time or place, or merely material concerning offences of the same kind or similar offences. Where the items seized relate to a person other than the person named in the warrant, it may also be checked whether that person stands in the relationship of an accomplice, an indirect principal or a necessary accomplice.

Third, the right of participation and the inventory may be queried. It may be checked from the record who voluntarily produced the information storage medium, whether the suspect actually controlled and managed that medium at the time of the seizure or up to a time proximate to it, and whether the suspect was given an opportunity to participate and an inventory of the electronic information. It may be borne in mind that the test is not the attribution of rights under civil law but the outward, objective de facto state of affairs.

Fourth, the limits of searching and derivative evidence may be queried. It may be compared in chronological order when and to what extent the investigative agency searched, whether it ceased searching and obtained a separate warrant after discovering information relating to a separate offence, and, if the evidence at issue was obtained on the basis of illegal primary evidence, whether there were intervening circumstances attenuating or severing the causal link. This is only a list of materials to check; conclusions are for the reader to draw.

Glossary

Nexus refers to whether the object of a seizure and search is related to the suspected facts stated in the warrant and has at least the minimum value of being capable of proving them. Judgment 2021Do8284 explained it by dividing it into objective nexus and personal nexus.

The person from whom the items were substantively seized is an expression used in the case law for a person who, even without having personally produced the information storage medium, can be regarded as the substantive party to the seizure and search of the electronic information stored on that medium as a whole. Judgment 2020Do1669 held that the right of participation and related rights must also be guaranteed to such a suspect.

Derivative evidence means evidence obtained in turn on the basis of primary evidence collected without following due procedure. In principle it cannot be used as evidence for a finding of guilt, and whether an exception applies is determined with a focus on whether the causal link has been attenuated or severed.

In this brief, a military prosecutor refers to the person designated by Article 254(1) of the Military Court Act as the actor conducting a seizure and search. Under the current provision, a military prosecutor may conduct a seizure, search or inspection under a warrant issued by a military judge of the competent military court, and a military judicial police officer, under paragraph (2) of the same Article, applies to a military prosecutor and acts under a warrant issued upon the military prosecutor's request.

Sources and limitations

The statutory sources are the current texts on the National Law Information Center. Articles 2, 146, 149, 162, 163, 170, 254, 257, 258 and 359-2 of the Military Court Act (effective 2 October 2026, Act No. 22013), Articles 106, 121, 129, 215, 218, 219 and 308-2 of the Criminal Procedure Act (effective 2 October 2026, Act No. 22009), and Articles 243 and 244 of the Criminal Act (effective 2 October 2026, Act No. 22007) were checked on 16 October 2026.

The judicial sources are the summaries of holdings, summaries of judgment and operative parts of Supreme Court Judgments 2020Do1669 and 2021Do8284 published on the National Law Information Center. The wording of Article 254(1) of the former Military Court Act has been reproduced only to the extent quoted in the summary of judgment of Judgment 2021Do8284; the original text of the former Act was not separately checked.

The defendants' status in the two cases, the course of proceedings in the courts before which the cases were pending, and the specific content of the seized documents and electronic information do not appear in the summaries of holdings or summaries of judgment and have therefore not been included. The provisions of the Military Secret Protection Act and the Military Criminal Act were also not checked for this brief.

Points left open

Judgment 2021Do8284 derived the nexus requirement under the former Military Court Act through the provisions applied mutatis mutandis. Now that current Article 254 expressly contains nexus wording, how the principle of printing out or copying within a specified scope under Article 146(3), applied mutatis mutandis, and the participation procedures under Articles 162 and 163 apply together in military investigations is a point requiring further examination.

How the test of the person from whom the items were substantively seized in Judgment 2020Do1669 will apply to an information storage medium over which several persons share control remains an open question. This is because the assessment of actual control and management and of exclusive rights of management and disposal may differ between equipment issued and managed by an organisation and privately owned equipment.

After the amendment of the Criminal Procedure Act on 4 August 2026 reorganised the provisions on investigating authorities, it also remains to be seen how the correspondence between the Military Court Act and the Criminal Procedure Act will be settled. Where a military case falls within the jurisdiction of the ordinary courts under Article 2(2) of the Military Court Act, a question may arise as to which provision of which Act governs the lawfulness of evidence collected by military investigative agencies.

There is also room to clarify whether the circumstances that would support a finding that the causal link to derivative evidence (fruit of the poisonous tree) has been attenuated or severed may be assessed differently in light of the characteristics of the military organisation, for example how cases involving a superior's orders or an internal unit inquiry should be treated.

When to reconsider

This brief will be rewritten if the provisions of the Military Court Act on search and seizure and on evidence, or the corresponding provisions of the Criminal Procedure Act, are amended, or if the Supreme Court issues a new ruling on relevance or the right to participate in relation to seizures by military prosecutors or military judicial police officers.

At that point, the correspondence between the provisions of the two Acts and the differences in the law in force at the time of the conduct will be restated within the scope of what the Holdings and the Summary of Judgment in the original text of the judgment state.

Statutes referred to

• 군사법원법 제2조, 제146조, 제149조, 제162조, 제163조, 제170조, 제254조, 제257조, 제258조, 제359조의2
• 형사소송법 제106조, 제121조, 제129조, 제215조, 제218조, 제219조, 제308조의2
• 형법 제243조, 제244조

Decisions referred to

• 대법원 2023. 12. 14. 선고 2020도1669 판결 · Decision ledger
• 대법원 2025. 2. 27. 선고 2021도8284 판결 · Decision ledger

Verification status

The cited provisions (Article 2, Article 146, Article 149, Article 162, Article 163, Article 170, Article 254, Article 257, Article 258, and Article 359-2 of the Military Court Act; Article 106, Article 121, Article 129, Article 215, Article 218, Article 219, and Article 308-2 of the Criminal Procedure Act; and Article 243 and Article 244 of the Criminal Act) were compared against the current original text at the National Law Information Center on October 16, 2026. The cited decisions (Supreme Court 2020Do1669, 2021Do8284) were compared against the Holdings, Summary of Decision, and Operative Part of the original judgment text at the National Law Information Center.