Plea bargaining in the United States
The constitutionality of plea bargaining was established by "Brady v. United States" in 1970, although the Supreme Court warned that plea incentives which were sufficiently large or coercive as to over-rule defendants' abilities to act freely, or used in a manner giving rise to a significant number of innocent people pleading guilty, might be prohibited or lead to concerns over constitutionality. "Santobello v. New York" added that when plea bargains are broken, legal remedies exist.
Adversarial system
Proponents of inquisitorial justice dispute these points. They point out that many cases in adversarial systems, and most cases in the United States, are actually resolved by plea bargain or settlement. Plea bargain as a system does not exist in an inquisitorial system. Many legal cases in adversarial systems, and most in the United States, do not go to trial, which may lead to injustice when the defendant has an unskilled or overworked attorney, which is likely to be the case when the defendant is poor. In addition, proponents of inquisitorial systems argue that the plea bargain system causes the participants in the system to act in perverse ways, in that it encourages prosecutors to bring charges far in excess of what is warranted and defendants to plead guilty even when they believe that they are not.