Plea

These pleas claim that a case cannot proceed for some reason. They are so-called because, rather than being an answer to the question of guilt or innocence, they are a claim that the matter of guilt or innocence should not be considered.

They are:

• autrefois convict (or autrefois acquit) – where under the doctrine of double jeopardy, the accused has been previously convicted or acquitted of the same charge and hence cannot be tried again.
• plea of pardon – where the accused has been pardoned for the offense.

A defendant who enters a plea of guilty must do so, in the phraseology of a 1938 United States Supreme Court case, Johnson v. Zerbst, "knowingly, voluntarily and intelligently". The burden is on the prosecution to prove that all waivers of the defendant's rights complied with due process standards. Accordingly, in cases of all but the most minor offenses, the court or the prosecution (depending upon local custom and the presiding judge's preference) will engage in a plea colloquy wherein they ask the defendant a series of rote questions about the defendant's knowledge of his rights and the voluntariness of the plea. Typically the hearing on the guilty plea is transcribed by a court reporter, and the transcript is made a part of the permanent record of the case to preserve the conviction's validity from being challenged at some future time. "Intelligent" has been described as "an elusive term, meaning that the defendant knows his rights, the nature of the charge to which he is pleading, and the consequences of his plea."[7] "Voluntary" has been described as also "an elusive term which has come to mean not induced by 'improper' inducements, such as bribing or physical violence, but not including the inducements normally associated with charge and sentence bargaining (except for inducements involving 'overcharging' by prosecutors)."[8] Empirical research has demonstrated that violent conditions in jails during pretrial detention of people who are legally innocent do improperly induce or coerce guilty pleas,[9] but this has not constitutionally invalidated the pleas under current Supreme Court precedent.

Virtually all jurisdictions hold that defense counsel need not discuss with defendants the collateral consequences of pleading guilty, such as consecutive sentencing or even treatment as an aggravating circumstance in an ongoing capital prosecution.[10] However, the Supreme Court recognized an important exception in Padilla v. Kentucky (2010), in which the Court held that defense counsel is obligated to inform defendants of the potential immigration consequences of a guilty plea. Thus a defendant who is not advised of immigration consequences may have an ineffective assistance of counsel argument.

In the U.S. federal system, the court must also satisfy itself that there is a factual basis for the guilty plea.[4] However, this safeguard may not be very effective because the parties, having reached a plea agreement, may be reluctant to reveal any information that could disturb the agreement. When a plea agreement has been made, the judge's factual basis inquiry is usually perfunctory, and the standard for finding that the plea is factually based is very low.[11]

Other special pleas used in criminal cases include the plea of mental incompetence, challenging the jurisdiction of the court over the defendant's person, the plea in bar, attacking the jurisdiction of the court over the crime charged, and the plea in abatement, which is used to address procedural errors in bringing the charges against the defendant, not apparent on the "face" of the indictment or other charging instrument. Special pleas in federal criminal cases have been abolished, and defenses formerly raised by special pleas are now raised by motion to dismiss.

A conditional plea is one where the defendant pleads guilty to the offense but expressly reserves the right to appeal certain aspects of the charges (for example, that the evidence was illegally obtained).

In United States v. Binion, malingering or feigning illness during a competency evaluation was held to be obstruction of justice and led to an enhanced sentence. Although the defendant had pleaded guilty, he was not awarded a reduction in sentence because the feigned illness was considered to mean that he was not accepting responsibility for his illegal behavior.[12]

A defendant who enters a plea of guilty must do so unequivocally. A guilty plea which is "imperfect, unfinished or otherwise ambiguous"[13] will not legitimate and should the court proceed to sentence on such a plea, there exist grounds for ordering a retrial or quashing the conviction.

In R v Atkinson,[14] the Court of Appeal held that, where a defendant entered a plea of 'Guilty, but i intended to defend myself' this could be held to be an unequivocal plea where the judge had clarified any ambiguity before accepting the plea.

Three special pleas (though not in the strictest sense of the word) exists in the criminal courts of England and Wales:

Demurrer: Which is an "objection to the form or substance of the indictment".[15] It is essentially no different than a motion to quash the indictment, however, it continues to exist in law. Unlike standard pleas, this must be entered in writing in advance of the arraignment.

Plea to jurisdiction:[16] Can be entered where the defendant believes the Crown Court does not have the power to hear the case before it, such a plea is usually entered where the offence being charged is summary only. Similarly to Demurrer, this plea must be entered in writing in advance.

Pardon: "It may be relied on where a pardon has been granted by the Crown on the advice of the Home Secretary in exercise of the royal prerogative of mercy. It must be pleaded at the first opportunity (i.e. before arraignment if the pardon has by then been granted). In modern times, the plea has become obsolete."[16]