The insanity defense, also known as the mental disorder defense, is an affirmative defense by excuse in a criminal case, arguing that the defendant is not responsible for their actions due to a psychiatric disease at the time of the criminal act. This is contrasted with an excuse of provocation, in which the defendant is responsible, but the responsibility is lessened due to a temporary mental state. It is also contrasted with the justification of self defense or with the mitigation of imperfect self-defense. The insanity defense is also contrasted with a finding that a defendant cannot stand trial in a criminal case because a mental disease prevents them from effectively assisting counsel, from a civil finding in trusts and estates where a will is nullified because it was made when a mental disorder prevented a testator from recognizing the natural objects of their bounty, and from involuntary civil commitment to a mental institution, when anyone is found to be gravely disabled or to be a danger to themself or to others.
Holmes v. South Carolina, 547 U.S. 319 (2006), was a decision by the United States Supreme Court involving the right of a criminal defendant to present evidence that a third party instead committed the crime. The Court vacated the rape and murder conviction in South Carolina of a man who had been denied the opportunity to present evidence of a third party's guilt, because the trial court believed the prosecutor's forensic evidence was too strong for the defendant's evidence to raise an inference of innocence. The Court ruled unanimously that this exclusion violated the right of a defendant to have a meaningful opportunity to present a complete defense, because the strength of a prosecutor's case had no logical relationship to whether a defendant's evidence was too weak to be admissible.
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.
Michael Mark Welner is an American forensic psychiatrist and Chairman of The Forensic Panel. Welner is best known for his work in sensitive and complex litigation. He has acted as lead forensic psychiatric examiner in numerous criminal or court proceedings of national and international prominence, including precedent-setting trials and higher court decisions. Welner is also known for a number of innovations in forensic science, forensic psychiatry and justice, including protocols for prospective peer review in forensic medicine consultation, research to standardize an evidence-based distinction of the worst crimes, The Depravity Standard, and recommendations for upgrading forensic science assessment. He has been featured in network television news coverage of forensic psychiatry issues, has authored publications for professional and public audiences, and has contributed to emerging legislation on mental health reform.
Colorado v. Connelly, 479 U.S. 157 (1986), was a U.S. Supreme Court case that was initiated by Francis Connelly, who insisted that his schizophrenic episode rendered him incompetent, nullifying his waiver of his Miranda rights.
In criminal law, a mitigating factor, also known as an extenuating circumstance, is any information or evidence presented to the court regarding the defendant or the circumstances of the crime that might result in reduced charges or a lesser sentence. Unlike a legal defense, the presentation of mitigating factors will not result in the acquittal of a defendant. The opposite of a mitigating factor is an aggravating factor.
Bigby v. Dretke 402 F.3d 551, the U.S. Court of Appeals for the Fifth Circuit heard a case appealed from the United States District Court for the Northern District of Texas on the issue of the instructions given to a jury in death penalty sentencing. The decision took into account the recent United States Supreme Court decisions concerning the relevance of mitigating evidence in sentencing, as in Penry v. Lynaugh.
Ohio v. Roberts, 448 U.S. 56 (1980), is a United States Supreme Court decision dealing with the Confrontation Clause of the Sixth Amendment to the United States Constitution.
Tennard v. Dretke, 542 U.S. 274 (2004), was a United States Supreme Court case in which the court was asked whether evidence of the defendant's low IQ in a death penalty trial had been adequately presented to the jury for full consideration in the penalty phase of his trial. The Supreme Court held that not considering a defendant's low IQ would breach his Eighth Amendment rights and constitute a cruel and unusual punishment.
Estelle v. Smith, 451 U.S. 454 (1981), was a United States Supreme Court case in which the Court held that, per Miranda v. Arizona (1966), the state may not force a defendant to submit to a psychiatric examination solely for the purposes of sentencing. Any such examination violates the defendant's Fifth Amendment rights against self-incrimination as well as the Sixth Amendment right to counsel, and is therefore inadmissible at sentencing.
Barefoot v. Estelle, 463 U.S. 880 (1983), is a United States Supreme Court case. The Court ruled on the admissibility of clinical opinions given by two psychiatrists hired by the prosecution in answer to hypothetical questions regarding the defendant's future dangerousness and the likelihood that he would present a continuing threat to society in this Texas death penalty case. The American Psychiatric Association submitted an amicus curiae brief in support of the defendant's position that such testimony should be inadmissible and urging curtailment of psychiatric testimony regarding future dangerousness and a prohibition of such testimony based on hypothetical data.
Mitchell v. United States, 526 U.S. 314 (1999), is a United States Supreme Court case that considered two Fifth Amendment privileges related to a criminal defendant’s rights against self-incrimination in a Federal District Court. The court ruled that a defendant who waives the guilty plea does not also waive the privilege during the sentencing phase of the trial, and that the court cannot draw an adverse inference from the defendant's silence when determining facts related to the crime which affect the severity of the sentence.
Drope v. Missouri, 420 U.S. 162 (1975), was a United States Supreme Court case in which the Court held a Missouri trial court deprived a defendant of due process by failing to order a competency examination after he was hospitalized following an attempted suicide and as a result missed a portion of his trial for a capital offense.
Cooper v. Oklahoma, 517 U.S. 348 (1996), was a United States Supreme Court case in which the Court reversed an Oklahoma court decision holding that a defendant is presumed to be competent to stand trial unless he proves otherwise by the second highest legal standard of proof, that of clear and convincing evidence, ruling that to be unconstitutional. The court said the defendant's Fourteenth Amendment rights to due process were violated.
United States criminal procedure derives from several sources of law: the baseline protections of the United States Constitution; federal and state statutes; federal and state rules of criminal procedure ; and state and federal case law. Criminal procedures are distinct from civil procedures in the US.
United States v. Felix, 503 U.S. 378 (1992), was a decision by the United States Supreme Court, which held that "a[n]…offense and a conspiracy to commit that offense are not the same offense for double jeopardy purposes." The Supreme Court rejected the Tenth Circuit's reversal of Felix's conviction, finding that the Court of Appeals read the holding in Grady v. Corbin (1990) too broadly.
Williams v. Florida, 399 U.S. 78 (1970), is a United States Supreme Court case in which the Court held that the Fifth Amendment does not entitle a defendant in a criminal trial to refuse to provide details of his alibi witnesses to the prosecution, and that the Sixth Amendment does not require a jury to have 12 members.
Penry v. Johnson, 532 U.S. 782 (2001), is a United States Supreme Court case which concerned whether instructions given to a Texas jury were constitutionally adequate to emphasize the mitigating factors in sentencing of defendants who are intellectually disabled The Texas courts had determined the sentencing instructions were consistent with prior Supreme Court jurisprudence, but the Court in a divided decision reversed, finding the sentencing instructions insufficient. This was the second time Penry's case made it to the Supreme Court.
United States v. Valenzuela-Bernal, 458 U.S. 858 (1982), is a United States Supreme Court case that determined the constitutionality of deporting aliens who might give testimony in criminal alien smuggling prosecutions. Because deporting alien witnesses might take away a testimony that would be both “material and favorable” to the defendant, it gives rise to a potential motion from the defense to dismiss the indictment under the Compulsory Process Clause of the Sixth Amendment and the Due Process Clause of the Fifth Amendment.
Kahler v. Kansas, 589 U.S. ___ (2020), is a case of the United States Supreme Court in which the justices ruled that the Eighth and Fourteenth Amendments of the United States Constitution do not require that states adopt the insanity defense in criminal cases that are based on the defendant's ability to recognize right from wrong. It was argued on October 7, 2019 and decided on March 23, 2020.
