The plea bargain (also plea agreement, plea deal, copping a plea, or plea in mitigation) is any agreement in a criminal case between the prosecutor and defendant whereby the defendant agrees to plead guilty to a particular charge in return for some concession from the prosecutor. This may mean that the defendant will plead guilty to a less serious charge, or to one of the several charges, in return for the dismissal of other charges; or it may mean that the defendant will plead guilty to the original criminal charge in return for a more lenient sentence.
A plea bargain allows both parties to avoid a lengthy criminal trial and may allow criminal defendants to avoid the risk of conviction at trial on a more serious charge. For example, in the U.S. legal system, a criminal defendant charged with a felony theft charge, the conviction of which would require imprisonment in state prison, may be offered the opportunity to plead guilty to a misdemeanor theft charge, which may not carry a custodial sentence.
In cases such as an automobile collision when there is a potential for civil liability against the defendant, the defendant may agree to plead no contest or "guilty with a civil reservation", which essentially is a guilty plea without admitting civil liability.
Plea bargaining can present a dilemma to defense attorneys, in that they must choose between vigorously seeking a good deal for their present client, or maintaining a good relationship with the prosecutor for the sake of helping future clients.
In charge bargaining, defendants plead guilty to a less serious crime than the original charge. In count bargaining, they plead guilty to a subset of multiple original charges. In sentence bargaining, they plead guilty agreeing in advance what sentence will be given; however, this sentence can still be denied by the judge. In fact bargaining, defendants plead guilty but the prosecutor agrees to stipulate (i.e., to affirm or concede) certain facts that will affect how the defendant is punished under the sentencing guidelines.
Plea bargaining has been defended as a voluntary exchange that leaves both parties better off, in that defendants have many procedural and substantive rights, but by pleading guilty, defendants "sell" these rights to the prosecutor, receiving concessions that they value more highly than the rights surrendered. It has been argued that plea bargaining benefits society by ensuring that the guilty are less likely to be acquitted.