Where Do Intent to Kill and Liability as a Principal Diverge — The Boundaries of Omission, Joint Principal Offender, and Aiding

Question

In cases where a person has died or a grave danger to life has arisen, the focus of the trial does not rest solely on the gravity of the harm caused. Where the defendant did not personally wield a weapon but caused death by failing to take rescue measures (Article 18 and Article 250(1) of the Criminal Act), where the defendant exchanged conversation and encouragement with another person before that person carried out a murder or suicide (Articles 30, 32 and 252(2) of the Criminal Act), or where the defendant, carrying a dangerous article, attempted to inflict bodily injury but the attempt failed (Article 258-2(1) and (3) of the Criminal Act), the question of which elements of offence and which applicable range of punishment apply is fiercely contested.

In such cases, the dividing line between guilt and innocence, and between one offence and another, lies in whether the defendant's inner dolus eventualis (conditional intent) to kill (Article 13 of the Criminal Act) and the control he or she exercised over the essential course of events have been proved on the record beyond reasonable doubt (Article 307(2) and Article 308 of the Criminal Procedure Act). If murder by omission is rejected, offences such as abandonment resulting in death (Article 271(1) and Article 275 of the Criminal Act) come into question; if liability as a joint principal offender by conspiracy to murder is rejected, the questions of whether the offence of aiding murder, as an accessory, is made out (Article 32 of the Criminal Act) and whether an amendment of the indictment is required (Article 298 of the Criminal Procedure Act) arise in turn.

Further, where the act of commission ended in an attempt, how statutory mitigation (Article 55(1), subparagraph 3 of the Criminal Act) alters the maximum and minimum of the applicable range of punishment determines the sentence imposed and the possibility of a suspended execution of sentence. Through Supreme Court judgments addressing murder by omission and the extent of mitigation for attempted aggravated injury, and through the issues surrounding the distinction between joint principal offenders by conspiracy and accessories, this brief examines what must be verified, and how competing interpretations should be compared, at trial in serious violent crime cases.

Material to check

First, records of the timing of rescue and reporting and of control at the scene. In cases where murder by omission (Article 18 and Article 250(1) of the Criminal Act) or abandonment resulting in death (Article 271(1) and Article 275 of the Criminal Act) is at issue, the communication logs, records of public-address announcements, CCTV footage, the arrival times of rescue units, and the defendant's movements and time of departure must be compared minute by minute, from the moment the danger arose until the moment of death or rescue. This timeline reveals whether the victim lacked the capacity to deal with the danger on his or her own, whether the defendant had a duty of protection or rescue arising from statute, contract or prior conduct, and whether the defendant stood by even though that duty could easily have been performed.

Second, records of the division of the act of commission and of communications and instructions. In murder or suicide-participation cases involving multiple participants (Articles 30, 32, 250(1) and 252(2) of the Criminal Act), text messages, messenger conversations and call records before and after the offence, the times at which photographs and videos were sent, the preparation of the instruments of the offence, and whether the participant accompanied the principal to the scene must be assembled in chronological order. In particular, only by isolating, verbatim, what words the participant addressed to the principal and what material or psychological assistance was given at the decisive moment when the principal proceeded to commission can mere acquiescence be distinguished from aiding and, further, from joint principal offending by conspiracy with functional control over the act.

Third, records of the characteristics of the weapon or dangerous article and of how the injury or attempt came about. In cases of aggravated injury committed while carrying a dangerous article, and attempts thereof (Article 258-2(1) and (3) of the Criminal Act), the seizure records and photographs concerning the material, size and presence or absence of a blade of the article used, the parts of the body attacked and the number of blows, the distance from the victim, how the offence came to be discontinued (whether through the victim's subduing the defendant, a third party's intervention, or voluntary abandonment), and the medical certificates and medical records are examined together. Where no injury resulted, whether the attempt was one frustrated by obstacles or one voluntarily abandoned, and how the court of first instance and the court below calculated the applicable range of punishment by applying statutory mitigation (Article 55(1), subparagraph 3 of the Criminal Act), are compared in the "application of law" section of the judgments.

Fourth, records of the structure of the primary and alternative facts charged in the indictment and of the subject matter of adjudication. Whether the prosecutor, while charging murder or joint principal offending as the primary charge, added abandonment resulting in death or aiding as an alternative charge (Article 254(5) and Article 298 of the Criminal Procedure Act), or whether the matter falls within the scope in which the court may of its own motion find a lesser included fact without an amendment of the indictment, must be confirmed from the indictment and the trial records. Because the primary and alternative facts charged differ in the content of the intent and the degree of control over the act that must be proved, the exercise of the right of defence and the direction of the examination of evidence are likewise divided in accordance with that structure.

Possible readings

At the boundary between murder by omission on the one hand and abandonment resulting in death or death caused by occupational negligence on the other, interpretations clash over the weight of the breach of the duty to act and the existence or absence of dolus eventualis (conditional intent). The prosecution reads the facts as follows: if a person bearing a legal duty of protection, while clearly aware of an emergency from which the victim could not escape unaided, left the scene without taking rescue measures, that person had dolus eventualis (conditional intent) in that he or she foresaw and accepted the occurrence of death, and the omission carries criminal-law value equivalent to murder by commission. The defence, by contrast, counters that, given the confusion at the scene at the time, the limits on obtaining information, the vacuum in the chain of command or the fluidity of the division of duties, the defendant had no inner will to accept the occurrence of death and could not independently control the essential course of events, so that the case should be dealt with not as murder but as abandonment resulting in death or within the category of negligence.

Views on the boundary between joint principal offenders by conspiracy and accessories in cases of aiding murder or aiding suicide are also sharply divided. The prosecution takes the view that, once the participant shared a concrete plan before the offence, discussed the means or method of the offence and urged its commission, an intention of joint commission and functional control over the act are established, and liability as a joint principal offender (Article 30 of the Criminal Act) arises even though the participant did not personally lay hands on the victim at the scene. The defence, by contrast, interprets the matter as follows: words or conduct that merely failed to dissuade, or responded favourably to, another person's announcement of an intended offence do not prove a relationship of mutual exploitation aimed at jointly realising the offence as one's own crime, and even if the participant strengthened the principal's resolve to commit the offence, this does not go beyond the limits of an accessory who facilitated the act of commission (Article 32 of the Criminal Act).

Interpretations concerning whether aggravated injury committed while carrying a dangerous article was completed or merely attempted, and concerning the extent of mitigation of the statutory punishment, likewise form an important fork in practice. As regards discretionary mitigation of the statutory punishment for attempted aggravated injury (Article 258-2(3) and (1) of the Criminal Act), namely imprisonment with labour for not less than one year and not more than ten years, one line of interpretation holds that, in accordance with the wording of the statutory mitigation provision (Article 55(1), subparagraph 3 of the Criminal Act), both the maximum and the minimum must be reduced by one half, fixing the applicable range of punishment at imprisonment with labour for not less than six months and not more than five years, and that if there is no need to lower the minimum, the court simply need not mitigate at all. Another line of interpretation holds that, because the purpose of discretionary mitigation is to give the judge discretion as to the extent of mitigation, an interpretation that leaves the maximum unchanged and lowers only the minimum should also be permitted, and thus reads the structure for calculating the applicable range of punishment differently.

What the decisions held

Supreme Court en banc judgment 2015Do6809 of 12 November 2015 held that, for an offence of improper omission to be established, a person under a legal duty to act to protect the legal interests of another who lacks the capacity to deal with the infringement of those interests by himself or herself must, although able easily to prevent the result, have controlled the essential course of events in a planned manner or stood by, such that the omission carries criminal-law value equivalent to an infringement of legal interests by commission; and a causal relationship must be established in that the result would not have occurred had the duty to act been performed. The Supreme Court found that, in the ship-sinking incident, Defendant 1, the captain, was under a duty to draw up a rescue plan and to take active and continuous rescue measures until the safety of everyone in the community aboard the ship had been secured, and that, although he could easily have made an abandon-ship announcement and the like, he left the passengers waiting aboard to their fate and abandoned ship first, so that the crime of murder by omission with dolus eventualis (conditional intent) was established. By contrast, as regards the senior crew members, Defendant 2, Defendant 3 and Defendant 9, the Supreme Court upheld the court below, which had acquitted them on the murder charges, on the ground that, in light of factors such as that their duties at the scene could change or be reassigned depending on the situation and that the captain had given no order to abandon ship, it was difficult to conclude that they had controlled the essential course of events or had, in conspiracy with the captain, stood by with dolus eventualis (conditional intent) to kill.

Supreme Court judgment 2018Do7658 of 13 September 2018 held that, for liability as a joint principal offender by conspiracy to be established, the subjective element, namely that two or more persons, with an intention of joint commission, carry out the offence by making use of one another, and the objective element of functional control over the act must be proved beyond reasonable doubt, and that it is not sufficient merely to have been aware of another person's offence and to have acquiesced in it without stopping it. The Court went on to hold that aiding under Article 32 of the Criminal Act comprises every direct or indirect act that facilitates the principal's act of commission, including not only tangible, material aiding but also intangible, psychological aiding that strengthens the resolve to commit the offence; that an act performed before the commencement of commission, in anticipation of a future act of commission and so as to facilitate it, constitutes aiding once the principal has proceeded to commission; and that conditional awareness suffices for the intent to aid. In addition, the Court held that, where the basic facts of the charge are identical and there is no substantial disadvantage to the defendant's exercise of the right of defence, the court may find that criminal facts charged as joint principal offending constitute aiding even without an amendment of the indictment under Article 298 of the Criminal Procedure Act. On that basis, it upheld the court below, which, as regards Defendant 1, who had strengthened the resolve of the principal, who had announced the murder and sent photographs of herself in disguise, rejected liability as a joint principal offender by conspiracy to murder but found the offence of aiding murder established.

Supreme Court en banc judgment 2018Do5475 of 21 January 2021 clarified the interpretive standard for discretionary mitigation and Article 55(1), subparagraph 3 of the Criminal Act in a case of attempted aggravated injury (Article 258-2(3) and (1) of the Criminal Act), in which the defendant, carrying a kitchen knife as a dangerous article, attempted to inflict bodily injury but the attempt failed. The Supreme Court held that a discretionary mitigation provision stating that the punishment may be mitigated confers on the judge discretion as to whether to mitigate, and that, where the judge chooses to mitigate, both the maximum and the minimum terms of imprisonment for a limited term must be reduced by one half in accordance with Article 55(1), subparagraph 3 of the Criminal Act. Explaining that, in light of the legislative purpose of distinguishing between mandatory and discretionary mitigation, where a ground for discretionary mitigation exists but there is judged to be no need to lower the minimum of the applicable range of punishment, the court may simply determine the sentence by taking that ground into account as a sentencing factor without applying statutory mitigation, the Court upheld the decision of the court of first instance, which had applied mitigation for attempt to the statutory punishment for attempted aggravated injury (imprisonment with labour for not less than one year and not more than ten years) and imposed a sentence within the applicable range of punishment in which both the maximum and the minimum had been lowered.

Practical checklist

First, in an omission case, have the legal basis of the duty to act and the feasibility of its performance been identified on the record? It should first be checked, against communication logs, footage and the like, whether the defendant had a duty of protection arising from statute, contract or official duties, whether the victim was in a state in which he or she could not avoid the danger unaided, and at what time and under what physical conditions the defendant could easily have taken concrete measures (announcements, reporting, rescue instructions and the like) to prevent the danger from materialising.

Second, how are control over the events and the division of roles distributed within the chain of command or among multiple participants? By separating the scope of authority of the person in overall command from that of supporting staff, the replaceability of duties at the scene, and the existence of any prior plotting or real-time instructions, it should be examined whether a particular defendant controlled the essential course of events in a planned manner or remained at the level of acquiescing in, or psychologically assisting, another person's commission.

Third, are there gaps in the right of defence regarding the primary and alternative facts charged and the scope within which a lesser included fact may be found? It should be confirmed whether, in a case charged as joint principal offending, the court may find aiding without an amendment of the indictment (Article 298 of the Criminal Procedure Act), or whether, in a case charged as murder by omission, an alternative offence such as abandonment resulting in death is also charged, and it should be examined whether material rebutting the intent required for each offence (direct intent or dolus eventualis (conditional intent), and the intent of a principal or the intent to aid) has been submitted without omission.

Fourth, how have grounds for statutory mitigation, such as attempt and accessory liability, been reflected in calculating the applicable range of punishment? It should be verified by calculation whether, in respect of attempted aggravated injury committed while carrying a dangerous article (Article 258-2(3) and (1) of the Criminal Act) or mitigation for an accessory (Article 32(2) of the Criminal Act), both the maximum and the minimum of imprisonment for a limited term were reduced by one half in accordance with Article 55(1), subparagraph 3 of the Criminal Act, and whether the choice as to discretionary mitigation and the order of aggravation for concurrent crimes are accurately stated in the "application of law" section of the judgment.

Glossary

Offence of improper omission, guarantor position and dolus eventualis (conditional intent): Under Article 18 of the Criminal Act, an offence of improper omission arises where a person under a legal duty to act to prevent the occurrence of danger (a guarantor position) brings about the result defined in the elements of the offence by failing to do what he or she ought to have done. For the crime of murder by omission (Article 250(1) of the Criminal Act) to be established, in addition to such a guarantor position, the omission must carry criminal-law value equivalent to killing by commission, and dolus eventualis (conditional intent) (Article 13 of the Criminal Act), namely the inner will to accept the possibility, of which the person is aware, that the victim will die as a result of his or her omission, must be proved.

Functional control over the act of a joint principal offender by conspiracy, and the distinction from an accessory: A joint principal offender by conspiracy under Article 30 of the Criminal Act refers to the doctrine under which, where two or more persons, with an intention of joint commission, conspire to realise an offence together and then carry it out by dividing roles, so that functional control over the act through an essential contribution is recognised, each of them is punished as a principal. By contrast, an aider (accessory) under Article 32 of the Criminal Act refers to a person who does not go so far as to become master of the offence and control it, but assists the principal's act of commission tangibly or materially, or gives intangible, psychological assistance that strengthens the resolve to commit the offence; the punishment of an accessory is mandatorily mitigated in comparison with that of the principal.

Statutory punishment for attempted aggravated injury and statutory mitigation: Article 258-2(1) of the Criminal Act provides that a person who inflicts bodily injury on another by displaying the force of an organisation or a large number of persons, or while carrying a dangerous article, shall be punished by imprisonment with labour for not less than one year and not more than ten years, and paragraph (3) of the same Article punishes an attempt thereof. Where the judge chooses to mitigate the punishment for an attempt, the applicable range of punishment is fixed by reducing both the maximum and the minimum terms of imprisonment for a limited term by one half, in accordance with Article 55(1), subparagraph 3 of the Criminal Act, which prescribes the method of statutory mitigation.

Sources and limitations

This brief is based on the text of Articles 13, 18, 30, 32, 55(1), subparagraph 3, 250(1), 252(2), 254, 258-2(1) and (3), 271(1) and 275 of the Criminal Act and Articles 254(5), 298, 307(2) and 308 of the Criminal Procedure Act, as confirmed at the National Law Information Center as at 15 October 2026, and on Supreme Court en banc judgment 2015Do6809 of 12 November 2015, Supreme Court judgment 2018Do7658 of 13 September 2018 and Supreme Court en banc judgment 2018Do5475 of 21 January 2021.

The content set out here is a general commentary analysing, for research and study purposes, the analytical framework set out in the statutes and the texts of the judgments; it does not provide legal advice on any individual criminal case or offer conclusions on guilt, innocence or sentencing. In an actual case, a determination must be made by directly comparing the wording of the indictment, the list of evidence, the results of on-site expert examinations and the original texts of the records of statements.

Points left open

In disasters or organised incidents involving many people, the point at which the omissions of the person in overall charge and of middle managers acquire value equivalent to the act of commission of murder, and the objective indicators by which the duty to act of front-line staff and their control over the events are to be recognised where there is a vacuum in command, remain open issues requiring meticulous comparison of the facts in each case. In addition, where a person has urged another to carry out a murder or suicide through non-face-to-face online conversations or real-time video sharing, the line beyond which such conduct goes further than psychological aiding and can be assessed as functional control over the act, as indirect principal liability, or as murder by deceptive artifice continues to be contested.

In the domain of sentencing and the applicable range of punishment, further tasks to be examined together in subsequent case law and legislative discussion include how the practice whereby, where a ground for discretionary mitigation exists, the judge does not mitigate but merely takes the ground into account as a sentencing factor affects the defendant's right of defence and the predictability of sentencing, and how, in a structure in which the minimum statutory punishment for aggravated injury (Article 258-2 of the Criminal Act) is set at imprisonment with labour for not less than one year with no fine available, whether an article qualifies as dangerous and whether mitigation for attempt is applied constrain the possibility of a suspended execution of sentence or a suspended sentence.

When to reconsider

If the provisions of the Criminal Act on the elements of, and statutory punishments for, murder, participation in suicide and aggravated injury, or on attempts, accessories and statutory mitigation (Article 55(1), subparagraph 3 of the Criminal Act), are amended, the statutory comparison and the explanation of the applicable range of punishment in this brief will be rewritten.

If a new Supreme Court judgment is rendered on the standards for determining equivalence and dolus eventualis (conditional intent) in murder by omission, on the scope within which online participation gives rise to liability as a joint principal offender by conspiracy or as an accessory, or on the method of discretionary mitigation, the readings and the checklist will be updated to reflect its holdings and the summary of the judgment.

Statutes referred to

• 형법 제13조, 제18조, 제30조, 제32조, 제55조 제1항 제3호, 제250조 제1항, 제252조 제2항, 제254조, 제258조의2 제1항·제3항, 제271조 제1항, 제275조
• 형사소송법 제254조 제4항, 제298조, 제307조 제2항, 제308조

Decisions referred to

• 대법원 2015. 11. 12. 선고 2015도6809 전원합의체 판결 · Decision ledger
• 대법원 2018. 9. 13. 선고 2018도7658 판결 · Decision ledger
• 대법원 2021. 1. 21. 선고 2018도5475 전원합의체 판결 · Decision ledger

Verification status

The text of Articles 13, 18, 30, 32, 55, 250, 252, 254, 258-2, 271 and 275 of the Criminal Act and Articles 254, 298, 307 and 308 of the Criminal Procedure Act, together with the texts of Supreme Court en banc judgment 2015Do6809, judgment 2018Do7658 and en banc judgment 2018Do5475, was checked against the National Law Information Center as at 15 October 2026. This brief cites only the three judgments listed among the decisions discussed.