Prosecutors are attorneys who represent the People and attempt to prove in court that defendants are guilty of the crimes they're accused of. These professionals work for district, state and federal courts. District attorneys are responsible for most prosecutions in the United States, according to Harvard University Law School. Prosecutors question suspects, witnesses and experts and present incriminating evidence to judges and juries during civil and criminal trials. Their primary goal is to seek justice.
A prosecutor conducts extensive research before going to trial and presents her findings before judges and jurors. Prosecutors prepare compelling, persuasive opening and closing statements and offer evidence to contradict the defense attorney's claims, interpretations of the law and questionable evidence. They use statutes of the law and rulings in similar cases to support their arguments. A prosecutor should never hide or fail to disclose evidence that "negates guilt or mitigates the offense;" to do so is grounds for disbarment," according to the American Bar Association.
Calling Witnesses to the Stand
After the opening statements by both the prosecution and defense, prosecutors call witnesses to the stand to verify and validate alleged claims and evidence against the defendant. They focus on facts, eye-witness testimony and evidence gathered at the scene -- or evidence obtained from other locations, such as computer files -- that the witness has first-hand knowledge of. They might show witnesses photographs, diagrams or evidence to identify. A judge might allow the prosecutor to question a witness about the defendant's character or state of mind.
Cross-Examining the Defense Witnesses
Prosecutors cross-examine witnesses and experts that the defense puts on the stand. The goal is to question the credibility and truthfulness of the witnesses and determine if their testimony shows undue bias or reflects unjustifiable opinions. Prosecutors try to uncover lies, misleading statements and irrelevant information that doesn't accurately represent the facts of the case.
Punishments and Sanctions
A judge ultimate determines the sentence in a trial -- if the defendant is found guilty -- but the prosecutor can propose specific punishments or sanctions. For example, in a first-time offense of driving under the influence (DUI) case with no accident or injuries, a prosecutor might suggest several days of jail time, suspension of the motorist's driver's license and community service. Prosecutors often use previous sentences for similar crimes when proposing penalties, punishments and sanctions for their cases.