A district attorney is the elected chief prosecutor for a county or judicial district who decides which criminal cases to file, carries them through court, recommends sentences, and represents the government — “the people” as a whole — rather than any individual victim.1Legal Information Institute. District Attorney (DA) So when people ask what a district attorney does, the short answer is almost everything that happens on the government’s side of a criminal case, from the moment police finish an arrest to the moment a judge imposes a sentence.
Who the DA Is and How They Take Office
In most states, voters elect their district attorney to a four-year term. A handful of states fill the position by appointment instead. Either way, the DA must be a licensed attorney, and the office is usually much larger than one person: assistant district attorneys handle most of the day-to-day courtroom work, while the elected DA sets priorities for the whole office. Those priorities are policy decisions in everything but name. A DA who decides to focus resources on violent crime and route low-level drug cases into treatment is making a choice that affects thousands of defendants, which is why these elections carry more weight than many voters realize.
Deciding Whether to File Charges
After an arrest, the DA’s office reviews police reports, physical evidence, and witness statements to decide whether to file formal charges. The legal threshold is probable cause: enough facts that a reasonable person would believe a specific individual committed the crime.2Congress.gov. Constitution Annotated – Amdt4.5.3 Probable Cause Requirement This is where prosecutorial discretion operates, and it is arguably the most consequential power the office holds.
From that review, the DA can file the charges police recommended, substitute different or lesser charges, or decline to prosecute. Declining doesn’t always mean the evidence is weak. Many offices run pretrial diversion programs that send qualifying defendants — often first-time offenders facing lower-level charges — into treatment, community service, or counseling instead of prosecution. If the participant completes the program, charges are typically dismissed and nothing goes on their record. Diversion criteria vary, but prosecutors commonly weigh the offense type, the defendant’s history, and whether identifiable victims consent.
Prosecuting the Case in Court
Once charges are filed, the DA’s office carries the case forward. The courtroom drama most people picture is rare. Roughly 90 to 95 percent of criminal convictions in both federal and state courts come from plea bargains rather than trials.3Bureau of Justice Assistance. Plea and Charge Bargaining Research Summary In a plea deal, the prosecutor negotiates with the defense for a guilty plea, often in exchange for reduced charges or a lighter sentencing recommendation. The practice keeps an overloaded system functioning, and it also means prosecutors shape the outcome of most cases long before any judge or jury weighs in.
When a case does go to trial, the prosecution must prove guilt beyond a reasonable doubt, the highest standard of proof in the legal system.4Legal Information Institute. Beyond a Reasonable Doubt Assistant DAs present the government’s case through opening and closing arguments, witness testimony, and physical evidence.
Discovery and the Brady Rule
Before trial, prosecutors must share relevant evidence with the defense through a process called discovery. Federal rules require the government to turn over the defendant’s own statements, documents and objects material to the defense, and the results of any examinations or tests.5Legal Information Institute. Federal Rules of Criminal Procedure Rule 16 – Discovery and Inspection State rules differ in detail but follow the same principle.
Separate from general discovery is the Brady rule, from the 1963 Supreme Court case Brady v. Maryland. Prosecutors must turn over any evidence that favors the defendant: anything suggesting innocence, undermining a government witness, or reducing a potential sentence. The duty applies whether the prosecutor withholds the evidence deliberately or simply overlooks it. A Brady violation discovered during trial can lead to a mistrial; discovered after conviction, which is more common, it often results in the conviction being overturned.6Legal Information Institute. Brady Rule
Grand Juries and Preliminary Hearings
Before a serious case can go to trial, prosecutors have to establish probable cause through one of two paths, and the DA usually picks which. In a grand jury proceeding, the prosecutor presents evidence to a panel of citizens in a closed session with no defendant or defense attorney present. If the grand jury finds probable cause, it returns an indictment and the case moves forward.7Administrative Office of the United States Courts. Handbook for Federal Grand Jurors
The alternative is a preliminary hearing in open court. A judge reviews the prosecution’s evidence while the defense attends, cross-examines witnesses, and challenges what’s presented. Grand juries hear only the government’s side, which makes an indictment more likely; preliminary hearings give the defense an early look at what the state has. The choice between them is itself a strategic call.
Working with Police on Investigations
The DA’s office doesn’t wait for an arrest to get involved. Prosecutors collaborate with police from early stages of an investigation, providing legal guidance to make sure evidence-gathering methods will hold up later in court. In complex cases involving organized crime, financial fraud, or homicides, prosecutors may help officers draft search warrant applications that establish the probable cause a judge requires before authorizing a search.8Legal Information Institute. Federal Rules of Criminal Procedure Rule 41 – Search and Seizure
Recommending a Sentence
After a conviction or guilty plea, the DA’s office makes a sentencing recommendation to the judge. The recommendation reflects the severity of the crime, the defendant’s criminal history, and any aggravating or mitigating circumstances. In the federal system, sentencing guidelines use a grid cross-referencing the offense level with the defendant’s criminal history category to produce a recommended range in months.9United States Sentencing Commission. Annotated 2025 Chapter 5 Most states use similar structured frameworks.
A prosecutor may argue for a sentence at the high end of the range when aggravating factors apply, such as a particularly vulnerable victim or unusual cruelty. Final authority rests with the judge, but the DA’s recommendation carries real weight. Victims also have the right to address the court at sentencing, either in person or through a written victim impact statement.10U.S. Department of Justice. Victim Impact Statements
What the DA Does for Crime Victims
People often assume the DA is their lawyer after being victimized. The DA represents the state, not any individual victim. But federal law and most state laws give victims a defined set of rights the prosecutor’s office must help them exercise: timely notice of proceedings, the right to attend public hearings, the right to confer with the prosecutor, the right to be heard at plea and sentencing stages, and the right to seek restitution for financial losses caused by the crime.11Office of the Law Revision Counsel. 18 US Code 3771 – Crime Victims Rights
Most DA offices and all federal prosecutors’ offices run Victim-Witness Assistance Programs to carry out these obligations. Advocates inside those programs provide case updates, court preparation, referrals to counseling or financial assistance, and help navigating restitution.12United States Department of Justice. Victim Witness Assistance
The Duty to Seek Justice, Not Convictions
This is the single most important thing to understand about the role. A DA’s job is not to rack up convictions. The Supreme Court said as much in 1935, holding that the prosecutor’s interest “in a criminal prosecution is not that it shall win a case, but that justice shall be done.” A prosecutor “may strike hard blows” but “is not at liberty to strike foul ones.”13Justia Law. Berger v. United States, 295 US 78 (1935) That standard separates prosecutors from every other lawyer in the system. A defense attorney fights for a client. A prosecutor is supposed to fight for the right outcome.
The American Bar Association’s Model Rules of Professional Conduct translate the principle into concrete duties. A prosecutor may not pursue a charge they know lacks probable cause. They must make sure the accused has been advised of the right to counsel. They must promptly disclose evidence that tends to negate guilt or mitigate the offense. If a prosecutor later finds credible evidence that a convicted person is innocent, they must disclose it and work to remedy the wrongful conviction.14American Bar Association. Rule 3.8 – Special Responsibilities of a Prosecutor Every state adopts its own version of these rules, and prosecutors who violate them can face professional discipline up to disbarment.
What a DA Does Not Handle
District attorneys handle state-law crimes within their county or district — ordinary offenses from shoplifting and assault to murder. Federal crimes are a different track. The federal equivalent of the DA is the United States Attorney, appointed by the President with Senate confirmation to a four-year term covering a federal judicial district.15Office of the Law Revision Counsel. 28 US Code 541 – United States Attorneys U.S. Attorneys prosecute offenses like federal tax fraud, immigration violations, interstate drug trafficking, and crimes on federal property. Most criminal cases in the country involve state law, so the local DA’s office handles the overwhelming majority of prosecutions a person is likely to encounter.
Accountability for the DA’s Decisions
Given the power the office holds, how is it checked? Prosecutors performing core advocacy functions — filing charges, presenting evidence, arguing in court — have absolute immunity from civil lawsuits, even if their actions later turn out to be wrong. The Supreme Court established the doctrine in Imbler v. Pachtman.16Justia Law. Imbler v. Pachtman, 424 US 409 (1976) Absolute immunity does not reach actions outside the advocacy role, such as when a prosecutor functions as an investigator or administrator.
Immunity from civil suits is not immunity from all consequences. Prosecutors who commit misconduct face state bar discipline ranging from reprimand to suspension to disbarment. Brady violations and other ethical breaches can produce overturned convictions, dismissed cases, and court-imposed sanctions. And because most DAs are elected, voters can remove a prosecutor who abuses the office. It is a blunt check, but it is the most direct one the system offers.