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.
Lafler v. Cooper
Cooper argued that even though there is no right to a plea agreement itself, criminal defendants have the right to be assisted by competent counsel "during" plea negotiations. Accordingly, Cooper argued that criminal defendants can be prejudiced by ineffective assistance of counsel during plea negotiations, even if the subsequent trial was fair. Cooper also pointed out that every federal court of appeals to have considered the issue, and 25 of the 27 states to have considered the issue, agreed that counsel's deficient performance during plea negotiations can constitute "Strickland" prejudice.