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.
Arbitration in the United States
Typically, the validity of an arbitration clause is decided by a court rather than an arbitrator. However, if the validity of the entire arbitration agreement is in dispute, then the issue may remain subject to arbitration. For example, in "Rent-A-Center, West, Inc. v. Jackson", the Supreme Court of the United States held that "under the FAA, where an agreement to arbitrate includes an agreement that the arbitrator will determine the enforceability of the agreement, if a party challenges specifically the enforceability of that particular agreement, the district court considers the challenge, but if a party challenges the enforceability of the agreement as a whole, the challenge is for the arbitrator."