An Alford plea, in United States law, is a guilty plea in criminal court, whereby a defendant in a criminal case does not admit to the criminal act and asserts innocence. In entering an Alford plea, the defendant admits that the evidence presented by the prosecution would be likely to persuade a judge or jury to find the defendant guilty beyond a reasonable doubt.
The M'Naghten rule is any variant of the 1840s jury instruction in a criminal case when there is a defense of insanity:
that every man is to be presumed to be sane, and ... that to establish a defence on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know he was doing what was wrong.
The Sixth Amendment to the United States Constitution sets forth rights related to criminal prosecutions. It was ratified in 1791 as part of the United States Bill of Rights. The Supreme Court has applied most of the protections of this amendment to the states through the Due Process Clause of the Fourteenth Amendment.
In criminal law, diminished responsibility is a potential defense by excuse by which defendants argue that although they broke the law, they should not be held fully criminally liable for doing so, as their mental functions were "diminished" or impaired. The defense's acceptance in American jurisdictions varies considerably. The majority of states have adopted it by statute or case decision, and a minority even recognise broader defenses such as "irresistible impulse". Some American states restrict the defense to the charge of murder only where a successful defense will result in a manslaughter conviction instead of murder. Until recently, the Republic of Ireland did not accept the partial defense. The Irish Supreme Court had rejected the existence of the defense in DPP v O'Mahony. The case was recently abrogated, however, by enactment of the Criminal Law (Insanity) Act 2006, effective June 1, 2006. The act, in pertinent part, specifically adopted the partial defense for the charge of murder where a successful defense will result in a manslaughter conviction instead of murder.
In criminal law, entrapment is a practice whereby a law enforcement agent or agent of the state induces a person to commit a criminal offense that the person would have otherwise been unlikely or unwilling to commit. It "is the conception and planning of an offense by an officer or agent, and the procurement of its commission by one who would not have perpetrated it except for the trickery, persuasion or fraud of the officer or state agent."
An affirmative defense to a civil lawsuit or criminal charge is a fact or set of facts other than those alleged by the plaintiff or prosecutor which, if proven by the defendant, defeats or mitigates the legal consequences of the defendant's otherwise unlawful conduct. In civil lawsuits, affirmative defenses include the statute of limitations, the statute of frauds, waiver, and other affirmative defenses such as, in the United States, those listed in Rule 8 (c) of the Federal Rules of Civil Procedure. In criminal prosecutions, examples of affirmative defenses are self defense, insanity, and the statute of limitations.
In common law jurisdictions, an acquittal certifies that the accused is free from the charge of an offense, as far as the criminal law is concerned. This is so even where the prosecution is simply abandoned by the prosecution. The finality of an acquittal is dependent on the jurisdiction. In some countries, such as the United States, an acquittal operates to bar the retrial of the accused for the same offense, even if new evidence surfaces that further implicates the accused. The effect of an acquittal on criminal proceedings is the same whether it results from a jury verdict, or whether it results from the operation of some other rule that discharges the accused. In other countries, the prosecuting authority may appeal an acquittal similar to how a defendant may appeal a conviction.
The presumption of innocence is the legal principle that one is considered innocent unless proven guilty. It was traditionally expressed by the Latin maxim ei incumbit probatio qui dicit, non qui negat.
Apprendi v. New Jersey, 530 U.S. 466 (2000), is a landmark United States Supreme Court decision with regard to aggravating factors in crimes. The Court ruled that the Sixth Amendment right to a jury trial, incorporated against the states through the Fourteenth Amendment, prohibited judges from enhancing criminal sentences beyond statutory maxima based on facts other than those decided by the jury beyond a reasonable doubt. The decision has been a cornerstone in the modern resurgence in jury trial rights. As Justice Scalia noted in his concurring opinion, the jury-trial right "has never been efficient; but it has always been free."
Brady disclosure consists of exculpatory or impeaching information and evidence that is material to the guilt or innocence or to the punishment of a defendant. The term comes from the 1963 U.S. Supreme Court case Brady v. Maryland, in which the Supreme Court ruled that suppression by the prosecution of evidence favorable to a defendant who has requested it violates due process.
Cheek v. United States, 498 U.S. 192 (1991), was a United States Supreme Court case in which the Court reversed the conviction of John L. Cheek, a tax protester, for willful failure to file tax returns and tax evasion. The Court held that an actual good-faith belief that one is not violating the tax law, based on a misunderstanding caused by the complexity of the tax law, negates willfulness, even if that belief is irrational or unreasonable. The Court also ruled that an actual belief that the tax law is invalid or unconstitutional is not a good faith belief based on a misunderstanding caused by the complexity of the tax law, and is not a defense.
Actual innocence, also known as plain error, is a special standard of review in legal cases to prove that a charged defendant did not commit the crime(s) that he or she is accused of, which is often applied by appellate courts to prevent a miscarriage of justice. What makes the actual innocence standard interesting is that it may be invoked at any time, and not only in criminal proceedings but also in immigration and other civil proceedings.
The Confrontation Clause of the Sixth Amendment to the United States Constitution provides that "in all criminal prosecutions, the accused shall enjoy the right…to be confronted with the witnesses against him." Generally, the right is to have a face-to-face confrontation with witnesses who are offering testimonial evidence against the accused in the form of cross-examination during a trial. The Fourteenth Amendment makes the right to confrontation applicable to the states and not just the federal government. The right only applies to criminal prosecutions, not civil cases or other proceedings.
Clark v. Arizona, 548 U.S. 735 (2006), is a United States Supreme Court case in which the Court upheld the constitutionality of the insanity defense used by Arizona.
The Fifth Amendment to the United States Constitution addresses criminal procedure and other aspects of the Constitution. It was ratified in 1791 as part of the Bill of Rights. The Fifth Amendment applies to every level of the government, including the federal, state, and local levels, as well as any corporation, private enterprise, group, or individual, or any foreign government in regards to a US citizen or resident of the US. The Supreme Court furthered the protections of this amendment through the Due Process Clause of the Fourteenth Amendment.
United States federal laws governing offenders with mental diseases or defects provide for the evaluation and handling of defendants who are suspected of having mental diseases or defects. The laws were completely revamped by the Insanity Defense Reform Act of 1984 in the wake of the John Hinckley verdict.
Leland v. Oregon, 343 U.S. 790 (1952), was a United States Supreme Court case in which the Court upheld the constitutionality of placing the burden of persuasion on the defendant when they argue an insanity defense in a criminal trial. This differed from previous federal common law established in Davis v. United States (1895), in which the court held that if the defense raised an insanity defense, the prosecution must prove sanity beyond a reasonable doubt, but Davis was not a United States constitutional ruling, so only limited federal cases, but not state cases. Oregon had a very high burden on defense, that insanity be proved beyond a reasonable doubt. At that time, twenty other states also placed the burden of persuasion on the defense for an insanity defense.
The Insanity Defense Reform Act of 1984 was signed into law by President Ronald Reagan on October 12, 1984, amending the United States federal laws governing defendants with mental diseases or defects to make it significantly more difficult to obtain a verdict of not guilty only by reason of insanity. It removed the volitional component, that a defendant lacked capacity to conform their conduct to the law, from the ALI test. Defendants were exculpated only if "at the time of the commission of the acts constituting the offense, ... as the result of a severe mental disease or defect, [they were] unable to appreciate the nature and quality or wrongfulness of [their] acts." The law passed in the wake of public outrage after John Hinckley, Jr.'s acquittal by reason of insanity for his attempted assassination of President Ronald Reagan.
Commonwealth v. York, 50 Massachusetts (9Met) 93 (1845), is a precedent setting American criminal case in which it was determined that although the prosecution must establish all of the elements of a crime beyond a reasonable doubt, the defendant must prove the defense of provocation, which is about the defendant's mental state. This was consistent with Blackstone's Commentaries that the prosecution must prove the defendant committed a criminal act, and the defendant must then prove "circumstances of justification, excuse and alleviation". In federal courts, but not state all courts, this changed with Davis v. United States (1895), which set precedent that there is a presumption of innocence as to having a mental state of being "legally capable of committing crime".
