As an elected or appointed official, the prosecutor is the most powerful official in the criminal justice system. Prosecutors exercise unfettered discretion, deciding who to charge with a crime, what charges to file, when to drop the charges, whether or not to plea bargain, and how to allocate prosecutorial resources. In jurisdictions where the death penalty is in force, the prosecutor literally decides who should live and who should die by virtue of the charging decision.
Criminal justice professors Joseph Senna and Larry Siegel propose the true measure of a prosecutor. In their view, a litmus test for the integrity of a prosecutor is how he or she answers the following question: “When you exercise discretion, are you more concerned with fairness, the likelihood of conviction, or political considerations?”
Prosecutors exercise the most discretion in three areas of decision making: the decision to file charges, the decision to dismiss charges, and plea bargaining.
Once an arrest is made, a prosecutor screens the case to determine if it should be prosecuted or dropped. The decision to prosecute is based on the following factors:
The sufficiency of the evidence linking the suspect to the offense.
The seriousness of the offense.
The size of the court's caseload.
The need to conserve prosecutorial resources for more serious cases.
The availability of alternatives to formal prosecution.
The defendant's culpability (moral blameworthiness).
The defendant's criminal record.
The defendant's willingness to cooperate with the investigation or prosecution of others.
After a prosecutor files a charge, the prosecutor can reduce the charge in exchange for a guilty plea or enter a nolle prosequi (nol. pros.). A nolle prosequi is a formal statement by a prosecutor declaring that a case is discontinued. Reasons for entering a nol. pros. include insufficient evidence, inadmissible evidence, false accusations, and the trivial nature of some crimes.
Prosecutors also exercise discretion in negotiating pleas with defense counsel. A plea bargain is an agreement in which a prosecutor permits a defendant to plead guilty in exchange for a concession, such as reducing the charges or recommending a lenient sentence. There are advantages of plea bargaining to both the accused and the state. For the accused, it offers the possibilities of a reduced sentence and cheaper legal representation. For the government, it reduces the financial costs of prosecution, improves the efficiency of the courts by having fewer cases go to full trials, and allows the prosecution to devote its resources to the more serious cases.