Prosecutor Role and Duties

Prosecutor's Duties and Role in Adversarial Judicial System and in Advancing Rule of Law

I. Prosecutor’s Role in a Trial Case (Adversarial Model)

In an adversarial system modeled on the United States and aligned with international human rights standards, the prosecutor is not merely an advocate for conviction, but a minister of justice. The office functions within constitutional constraints, ethical rules, and due process guarantees.

A. Core Identity of the Prosecutor

Representative of the sovereign
Officer of the court
Minister of justice
Guardian of legality
Custodian of constitutional compliance

As articulated by the American Bar Association Standards for Criminal Justice, the prosecutor’s duty is to seek justice, not merely to convict.

II. Constitutional Foundations of Prosecutorial Duties

In a U.S.-modeled adversarial system, prosecutorial conduct is constrained by constitutional doctrine developed by the Supreme Court of the United States.

Key doctrinal anchors include:

Due Process Clause
Right to Counsel
Right to Confrontation
Compulsory Process
Equal Protection

Landmark case:

Brady v. Maryland
→ Establishes the constitutional duty to disclose exculpatory evidence.

III. Prosecutor’s Duties During Trial

1. Duty of Good Faith Litigation

The prosecutor must:

Avoid bad-faith tactics
Refrain from misleading the court
Present arguments grounded in law and evidence

Bad-faith conduct may violate due process.

4. Duty of Ethical Advocacy

Permissible:

Vigorous cross-examination
Persuasive argument
Lawful inferences from evidence

Prohibited:

Personal attacks
Appeals to prejudice
Inflaming jury passions
Shifting burden of proof

The burden always remains on the State.

7. Sentencing Phase Duties

Present aggravating evidence lawfully
Disclose mitigating evidence
Avoid arbitrary punishment requests
Ensure proportionality

2. Duty of Disclosure (Brady Obligation)

The prosecutor must disclose:

Exculpatory evidence
Impeachment evidence
Evidence material to guilt or punishment

Failure to do so constitutes constitutional error.

5. Duty to Protect the Presumption of Innocence

The prosecutor must:

Respect the defendant’s silence
Avoid commenting on failure to testify
Uphold proof beyond reasonable doubt

Case:

Griffin v. California
→ Prohibits prosecutorial comment on defendant’s silence.

3. Duty to Present Lawful Evidence Only

The prosecutor must not:

Use coerced confessions
Introduce illegally obtained evidence
Present perjured testimony knowingly

Case reference:

Napue v. Illinois
→ Prosecutor may not knowingly use false testimony.

6. Duty to Ensure Fair Jury Selection

No discriminatory peremptory strikes
Equal protection compliance