Prosecution
What does a prosecutor do?
A prosecutor decides whether a criminal case should be brought, on what charges, and presents it in court. This guide explains the tests applied, the duties owed, and how the role differs between systems.
In short
A prosecutor is the public official who decides whether a criminal case should be brought, on what charges, and who then presents that case in court on behalf of the public.
The prosecutor is not the lawyer for the victim and not an investigator, although in several systems prosecutors direct investigations. The role is defined by acting in the public interest, which sometimes means declining to bring a case that a victim wants brought, and sometimes means disclosing material that damages the prosecutor’s own case.
Why it exists
Separating the decision to charge from the decision to investigate places a check between the body that has built a theory of a case and the court that will decide it. The person applying that check has not spent months pursuing the suspect.
It also concentrates a consequential decision in a role that can be regulated, trained, and held to published standards. A prosecution imposes serious costs on a person before any determination of guilt, and a filter applied consistently is preferable to one applied case by case at the discretion of whoever investigated.
International guidance reflects this. The United Nations Guidelines on the Role of Prosecutors, adopted by the Eighth United Nations Congress on the Prevention of Crime and the Treatment of Offenders in 1990, address the impartiality expected of prosecutors, their duty to protect the public interest, and the separation of prosecutorial from judicial functions.
How it works
Several prosecution services — including those in the common-law systems whose published guidance uses this vocabulary — apply a two-stage test to the charging decision, in which the order matters: a case that fails the evidential stage is not saved by being important. This is not a universal structure. Germany’s Code of Criminal Procedure takes a different approach entirely: under § 152(2) StPO the prosecution is OBLIGED to act on all prosecutable offences where sufficient factual indications are present, and the provision asks nothing about the prospects of conviction. Where a system uses the two-stage vocabulary below, that is a fact about that system. How charging decisions work sets out the comparison.
- The evidential stage
- In the services that apply this test: is there sufficient admissible, reliable evidence to provide a realistic prospect of conviction? This is an objective assessment of the evidence, not a view about whether the person did it — and the phrase belongs to the systems that adopted it rather than to prosecution generally.
- The public-interest stage
- In those same services: even where the evidence is sufficient, is a prosecution the right response? Factors commonly include seriousness, harm, the suspect’s age and circumstances, the impact on the victim, and whether an alternative disposal is more appropriate. Under a principle of legality this question is not a general second stage at all — in Germany a public-interest judgement enters through defined statutory exceptions such as § 153 StPO.
Beyond charging, the prosecutor’s work includes selecting charges, advising investigators on what evidence would be needed, applying to the court for orders, presenting the case at trial, disclosing material to the defence, and in many systems making submissions on sentence.
The duty of disclosure is the one that most clearly distinguishes a prosecutor from an advocate for one side. Prosecutors are generally obliged to disclose material that undermines their own case or assists the defence, whether or not they intend to rely on it.
Common misconceptions
Widely held beliefs that do not match how the system actually operates.
Common belief: The prosecutor represents the victim.
In practice: Prosecutors act in the public interest. Many systems give victims rights to information, to be consulted, and to review a decision not to prosecute, but the prosecutor is not their lawyer and may take decisions the victim opposes.
Common belief: If there is evidence, a prosecution must follow.
In practice: Sufficient evidence is necessary but not sufficient. The public-interest stage exists precisely so that prosecution is not automatic, and discretion not to prosecute is a deliberate feature rather than a loophole.
Common belief: Prosecutors work for the police.
In practice: In most systems they are a separate service with distinct duties, including duties owed to the court and to the accused. Depending on the system, prosecutors direct investigations, advise on them, or receive completed files — but a prosecutor who simply endorsed investigators’ conclusions would not be performing the function.
Common belief: Dropping a case means the prosecutor believed the accused was innocent.
In practice: A case may be discontinued because a key witness cannot give evidence, because material is inadmissible, or because the public-interest test is not met. The decision concerns whether a prosecution can and should proceed, not a conclusion about what happened.
How this varies between jurisdictions
A required section on every guide. Arrangements differ between countries, and we say how.
The prosecution function is one of the most structurally variable parts of any justice system, and terminology transfers particularly badly here.
- Institutional position differs: a constitutionally separate service, a body within a ministry of justice, or a corps of judicial officers within the judiciary.
- Some systems apply a principle of mandatory prosecution where the evidence permits; others give prosecutors broad discretion. In practice most sit somewhere between, with exceptions to the stated rule.
- Whether prosecutors direct investigations, supervise them, or receive completed files is a fundamental structural difference that shapes the whole pre-trial process.
- Selection differs: career civil servants, judicial appointees, political appointees, or elected officials, depending on the country.
- Whether a decision not to prosecute can be challenged, and by whom, varies — through internal review, a court, or a victim’s right to bring a private prosecution.
- Negotiated resolutions range from formal plea agreements to systems that do not recognise them at all.
Rights and accountability
Because prosecutorial discretion is broad and largely exercised out of public view, it is structured by mechanisms that make it examinable.
- Published charging guidance, so decisions are made against stated criteria rather than case by case.
- Recorded reasons for significant decisions, particularly decisions not to prosecute.
- Review mechanisms allowing a decision not to prosecute to be reconsidered, in some systems on the application of the victim.
- Judicial supervision, including of applications for orders affecting the accused before trial.
- Disclosure obligations enforced by the court, with a failure capable of stopping proceedings or founding an appeal.
- Professional regulation, since prosecutors are usually subject to a professional conduct regime in addition to their employer’s.
Fair-trial guarantees under the International Covenant on Civil and Political Rights, including the requirement of adequate time and facilities to prepare a defence, are among the obligations that shape prosecutorial practice in states party to it.
Where to go next
Related: what courts do, what a criminal investigation is, and the presumption of innocence.
Related topics
- Why is the decision to bring a criminal case a public function?
Someone has to decide whether the state’s case should proceed, and the choice of who has consequences. Placing it in a public office separates it from the people who investigated, from the person harmed, and from the court that will decide.
- What has to be true before a criminal charge is brought?
There is no universal charging test. Germany obliges its prosecutors to act on sufficient factual indications; other systems apply an evidential assessment and a public-interest judgement; some give local prosecutors broad discretion with no national standard at all.
- Is a prosecutor a party to the case, or something else?
Several systems impose duties that cut against winning — establishing what exonerates as well as what incriminates, and disclosing material that damages the prosecution’s own case. Those duties are national, and this page attributes each to its source.
- What do courts do?
Courts resolve disputes, test the state’s case against individuals, interpret law, and review public decisions. This guide explains those functions and why judicial independence is structural.
- What is a criminal investigation?
A criminal investigation is a legally authorised process for establishing whether an offence occurred and gathering evidence that can be tested in court. This guide explains its structure, safeguards, and known failure modes.
- What is the presumption of innocence?
The presumption of innocence means a person charged with an offence is treated as not guilty until guilt is proved. This guide explains what it requires of courts, states, and reporting — and what it does not prevent.
Sources
Guidelines on the Role of Prosecutors
United Nations (adopted by the Eighth United Nations Congress on the Prevention of Crime and the Treatment of Offenders, Havana, 27 August – 7 September 1990) · International organisation · 1990 · link verified 2026-07-23
Supports the international standards expected of prosecutors: impartiality, protection of the public interest, respect for human dignity, and the separation of prosecutorial from judicial functions. Non-binding guidance, not a description of any national prosecution service.
United Nations · International organisation · 1966 · link verified 2026-07-23
Authentic treaty text as registered in the UN Treaty Series; registered ex officio 23 March 1976. Supports the fair-trial guarantees of Article 14, including the right to a competent, independent and impartial tribunal established by law, and the presumption of innocence (Art. 14(2)). Binding only on states party to it; does not support claims about states that have not ratified, nor about how any individual state applies it. WAVE 19 ADDITION, read from the same authentic treaty text in the UN Treaty Series PDF, text-extracted locally. Supports Article 14(5) in full: "Everyone convicted of a crime shall have the right to his conviction and sentence being reviewed by a higher tribunal according to law." The qualifier "according to law" is part of the provision and is load-bearing: the right is to review as the law of the state provides, not to appeal without limit or by any chosen route. Supports Article 14(6): where a person has by a FINAL decision been convicted of a criminal offence and the conviction has subsequently been reversed or the person pardoned on the ground that a new or newly discovered fact shows conclusively that there has been a miscarriage of justice, the person who has suffered punishment as a result shall be compensated according to law, unless it is proved that the non-disclosure of the unknown fact in time is wholly or partly attributable to that person. Supports Article 14(3)(g), that no one shall be compelled to testify against himself or to confess guilt, and Article 14(4), that the procedure for juvenile persons shall take account of their age and the desirability of promoting their rehabilitation. WAVE 20 ADDITION. PROVENANCE, stated precisely because this record's url is a different copy: the Article 4 material below was read on 2026-08-26 from OHCHR's official PDF of the Covenant at https://www.ohchr.org/sites/default/files/ccpr.pdf. The United Nations Treaty Series copy at this record's url timed out repeatedly this session and was not re-read, so nothing in this addition rests on it. Article 4 is the derogation clause, and its four cumulative conditions are the point. Supports ICCPR Art. 4(1): “1. In time of public emergency which threatens the life of the nation and the existence of which is officially proclaimed, the States Parties to the present Covenant may take measures derogating from their obligations under the present Covenant to the extent strictly required by the exigencies of the situation, provided that such measures are not inconsistent with their other obligations under international law and do not involve discrimination solely on the ground of race, colour, sex, language, religion or social origin.”. Supports ICCPR Art. 4(2), read with Arts. 6, 7, 8, 11, 15, 16 and 18 as printed in the same document: “2. No derogation from articles 6, 7, 8 (paragraphs 1 and 2), 11, 15, 16 and 18 may be made under this provision.”. Supports ICCPR Art. 4(3): “3. Any State Party to the present Covenant availing itself of the right of derogation shall immediately inform the other States Parties to the present Covenant, through the intermediary of the Secretary-General of the United Nations, of the provisions from which it has derogated and of the reasons by which it was actuated. A further communication shall be made, through the same intermediary, on the date on which it terminates such derogation.”. The Covenant binds States Parties to it. It is NOT evidence of any particular state's domestic law, and no country claim on this platform rests on it. It designates no organ to proclaim an emergency, assigns no role to any national legislature, and creates no civil-protection institution. The Human Rights Committee's interpretation of this article is cited separately and attributed to the Committee.WAVE 21 ADDITION. Read from the same United Nations Treaty Series PDF, text-extracted and searched. Supports Art. 9(1)-(4), and specifically that the Covenant polices ARBITRARINESS rather than closing a list of grounds: “Everyone has the right to liberty and security of person. No one shall be subjected to arbitrary arrest or detention. No one shall be deprived of his liberty except on such grounds and in accordance with such procedure as are established by law”; with 9(2) (informed at the time of arrest of the reasons and promptly of any charges), 9(3) (brought promptly before a judge or other officer authorised by law to exercise judicial power; it shall not be the general rule that persons awaiting trial shall be detained in custody) and 9(4) (entitlement to take proceedings before a court which decides without delay on the lawfulness of the detention). Supports Art. 14(1): “All persons shall be equal before the courts and tribunals”, with the right to a fair and public hearing by a competent, independent and impartial tribunal established by law, the closed grounds on which press and public may be excluded, and the rule that judgment shall be made public except where the interest of juvenile persons otherwise requires or the proceedings concern matrimonial disputes or the guardianship of children. Supports Art. 14(3)(e) (“To examine, or have examined, the witnesses against him and to obtain the attendance and examination of witnesses on his behalf under the same conditions as witnesses against him”), 14(3)(f) (free assistance of an interpreter) and 14(3)(g) (“Not to be compelled to testify against himself or to confess guilt” — note that the Covenant adds the confession limb, which the European Convention text does not contain). Supports Art. 14(5). VERIFIED NEGATIVES from exhaustive search of the Covenant text: “proportion” occurs zero times, “equality of arms” zero times, and “remain silent” zero times. This is treaty text binding states party to it; it is not evidence of any state's domestic law, and the corpus invariant forbidding a treaty from standing in for a country applies to it.
Strafprozessordnung (StPO) § 152 — Anklagebehörde; Legalitätsgrundsatz (German original text)
Bundesministerium der Justiz / Bundesamt für Justiz (Gesetze im Internet) · Legislation · link verified 2026-08-26
The authoritative German text of § 152 StPO, headed "Anklagebehörde; Legalitätsgrundsatz", read directly. Supports § 152(1): "Zur Erhebung der öffentlichen Klage ist die Staatsanwaltschaft berufen" — the public prosecution office is the body called upon to bring the public charge. And § 152(2) verbatim: "Sie ist, soweit nicht gesetzlich ein anderes bestimmt ist, verpflichtet, wegen aller verfolgbaren Straftaten einzuschreiten, sofern zureichende tatsächliche Anhaltspunkte vorliegen" — it is OBLIGED, unless the law provides otherwise, to take action in respect of all prosecutable offences, provided sufficient factual indications are present. Cited for the German principle of legality, for the fact that acting is a DUTY rather than a choice, and for the threshold being sufficient factual indications. It establishes no test framed in terms of the prospects of conviction, and it supports no claim about any other country.
Bundesministerium der Justiz / Bundesamt für Justiz (Gesetze im Internet) · Legislation · link verified 2026-08-26
The authoritative German text of § 153 StPO, read directly. Supports § 153(1): where the proceedings concern a Vergehen, the prosecution "kann … mit Zustimmung des für die Eröffnung des Hauptverfahrens zuständigen Gerichts von der Verfolgung absehen, wenn die Schuld des Täters als gering anzusehen wäre und kein öffentliches Interesse an der Verfolgung besteht" — may, with the consent of the court competent to open the main proceedings, refrain from prosecution where the offender's guilt would be regarded as minor and there is no public interest in prosecution; and that the court's consent is not required for a Vergehen not carrying an increased minimum penalty where the consequences caused are minor. Cited for the fact that Germany's legality principle carries express statutory exceptions involving a public-interest judgement, which is why the legality/opportunity distinction is not a binary. It supports no claim about how often the provision is used.
Strafprozessordnung (StPO) § 170 — Entscheidung über eine Anklageerhebung (German original text)
Bundesministerium der Justiz / Bundesamt für Justiz (Gesetze im Internet) · Legislation · link verified 2026-08-26
The authoritative German text of § 170 StPO, read directly. Supports § 170(1): where the investigations offer "genügenden Anlaß zur Erhebung der öffentlichen Klage" — sufficient reason to bring the public charge — the prosecution brings it by filing an indictment with the competent court. And § 170(2): otherwise the prosecution terminates the proceedings, notifying the accused where he has been questioned as such, where a warrant of arrest had been issued against him, where he has asked for a decision, or where a particular interest in notification is apparent. Cited for the German charging threshold and for the fact that a decision not to charge is a defined statutory outcome with its own notification duties. It supports no claim about the frequency of either outcome.