Criminal Complaint Process

What is a criminal complaint (고소)?

In Korean criminal procedure a complaint (고소) is a statement by the victim, or someone legally entitled to act for the victim, that tells investigators about a crime and asks that the offender be punished (Criminal Procedure Act art. 223). It's more than a tip: it creates procedural rights, such as the right to be told what happened to the case and to challenge a decision to drop it.

A complaint is the most common way a victim enters the criminal process. It doesn't make the victim a party to the case, though. As in American criminal procedure, the prosecution belongs to the state; the complainant is a participant with specific rights.

Who can file, and how

The victim can file, and so can a legal representative such as a parent of a minor (art. 225). If the victim has died, a spouse, lineal relatives or siblings may file, as long as it doesn't go against the victim's express wishes. A complaint can be submitted in writing or made orally to a prosecutor or judicial police officer, who must then prepare a record (art. 237). Most people file a written complaint (고소장) at the police station with jurisdiction.

A good complaint states who did what, when and where, attaches evidence such as messages, receipts or medical records, and specifies the offense where possible. Filing a knowingly false complaint is itself a crime, false accusation (무고죄, Criminal Act art. 156), punishable by up to 10 years in prison.

A complaint can also be withdrawn, but only until the first-instance judgment is pronounced, and once withdrawn it can't be refiled (art. 232). That matters most for the offense types described next.

Complaint-only and no-punishment-against-will offenses

Most crimes can be prosecuted whether or not the victim complains. Two groups are different:

• Complaint-only offenses (친고죄), such as insult (모욕죄, Criminal Act arts. 311–312(1)): prosecutors can't indict without a valid complaint, and the complaint must be filed within six months of learning who the offender is (art. 230).
• No-punishment-against-the-victim's-will offenses (반의사불벌죄), such as simple assault (art. 260) or defamation (arts. 307 and 312(2)): prosecution can proceed without a complaint, but it must stop if the victim clearly states they don't want punishment.

Because withdrawal ends these cases, settlement talks often focus on the victim's willingness to withdraw or to declare that they don't want punishment. Korea's truth-based defamation rules, and why they're controversial, are covered in truth-based defamation.

For a few crimes the law hands the victim a key to the courthouse door. That key is powerful, but once it's turned back after withdrawal, it can't be used again.

The investigation: police, referral and non-referral

Since the 2021 reform that rebalanced investigative powers between police and prosecutors, police handle the first-stage investigation of most crimes and can close cases themselves. A judicial police officer who receives a complaint must investigate promptly (art. 238). At the end, police either refer the case to prosecutors (송치) or decide not to refer it (불송치).

If police decide not to refer, they must send the records to prosecutors, who can review them within 90 days and request reinvestigation (art. 245-5). Police must notify the complainant of the non-referral and the reasons within 7 days (art. 245-6), and the complainant can file an objection (이의신청), which sends the case to prosecutors (art. 245-7). After a 2022 amendment, accusers (고발인) can no longer use this objection route.

The prosecutor's decision and challenging it

Once a case reaches prosecutors, they should decide whether to indict within three months of receiving the complaint (art. 257), although this is a guideline rather than a strict cutoff. They must notify the complainant of the decision within 7 days (art. 258) and, on request, explain the reasons for not indicting (art. 259). A decision not to indict (불기소) can rest on lack of evidence, the act not being a crime, or prosecutorial discretion to suspend indictment (기소유예).

A complainant who disagrees can appeal within the prosecution service (검찰항고) within 30 days under the Prosecutors' Office Act art. 10, and then seek a court ruling through an application for adjudication (재정신청, art. 260). If the high court grants it, the prosecutor must file charges. The court route is the main check on prosecutorial discretion in Korea.

1. Filing: Written or oral complaint to police or prosecutors.
2. Investigation: Police gather evidence and question the parties.
3. Referral or non-referral: Notice to complainant within 7 days of non-referral.
4. Charging decision: Prosecutors indict or decline, with notice within 7 days.
5. Challenges: Objection, prosecution appeal, application for adjudication.

A more detailed walk through every stage, from complaint to execution of a sentence, is in Criminal Case Procedure in Everyday Law: From Complaint and Arrest to Indictment, Non-Prosecution and Execution of Sentence in Korea, and evidence rules that come up once a case reaches trial are applied in Admissibility of a Deceased Accomplice's Police Interrogation Record in Korea: Articles 312 and 314 of the Criminal Procedure Act.

How the U.S. handles victim reports

The United States has no direct equivalent to the Korean complaint. Victims report crimes to police, but "pressing charges" is popular shorthand: the decision belongs to the prosecutor, who has broad discretion. In Linda R.S. v. Richard D. (1973), the Supreme Court said a private citizen lacks a judicially cognizable interest in the prosecution or nonprosecution of another. Federal felonies also require a grand jury indictment under the Fifth Amendment.

Victims do have statutory rights. The federal Crime Victims' Rights Act (18 U.S.C. § 3771) gives victims the right to be reasonably protected, to receive notice of proceedings, to be heard at release, plea and sentencing hearings, and to confer with the government's attorney, plus a way to assert those rights in court. Many states have added victims' rights to their constitutions.

Practical points and common mistakes

Complainants often run into the same problems. They miss the six-month window for complaint-only offenses, file without evidence and are frustrated when police can't proceed, or overstate facts in ways that create false-accusation risk. Others withdraw too early during settlement talks and lose the chance to complain again. Keeping copies of everything submitted, and asking for the case number, makes later objections much easier. The broader principle is the same one behind due process: rights are protected through clear procedures with deadlines.

A complaint is often the first time an ordinary person meets the criminal justice system head-on. Knowing the steps turns that encounter from a waiting game into a process you can follow.

What's the difference between 고소 and 고발?

A complaint (고소) is filed by the victim or legal representatives; an accusation (고발) can be filed by anyone who knows of a crime.

Is there a deadline to file a complaint?

For complaint-only offenses, six months from when the victim learns who the offender is. Other crimes follow the general statute of limitations.

Can I withdraw a complaint?

Yes, until the first-instance judgment, but once withdrawn the same complaint can't be filed again.

What if the police close my case?

You'll be notified within 7 days and can file an objection, which sends the case to prosecutors for review.

References and official sources

1. 형사소송법. 국가법령정보센터
2. 검찰청법. 국가법령정보센터
3. 형법. 국가법령정보센터
4. 18 U.S.C. § 3771, Crime victims' rights. Cornell LII
5. Linda R.S. v. Richard D., 410 U.S. 614 (1973). Justia
6. Crime Victims' Rights Act, Office for Victims of Crime. U.S. Department of Justice