Legally competent

In United States law, competence concerns the mental capacity of an individual to participate in legal proceedings or transactions, and the mental condition a person must have to be responsible for his or her decisions or acts. Competence is an attribute that is decision specific. Depending on various factors which typically revolve around mental function integrity, an individual may or may not be competent to make a particular medical decision, a particular contractual agreement, to execute an effective deed to real property, or to execute a will having certain terms. Depending on the state, a guardian or conservator may be appointed by a court for a person who satisfies the state's tests for general incompetence, and the guardian or conservator exercises the incompetent's rights for the incompetent. Defendants who do not possess sufficient "competence" are usually excluded from criminal prosecution, while witnesses found not to possess requisite competence cannot testify. The English equivalent is fitness to plead.

The word incompetent is used to describe persons who should not undergo certain judicial processes, and also for those who lack mental capacity to make contracts, handle their financial and other personal matters such as consenting to medical treatment, etc. and need a legal guardian to handle their affairs.

In United States law, the right to not be prosecuted while one is incompetent to stand trial has been ruled by the United States Supreme Court to be guaranteed under the due process clause. If the court determines that a defendant's mental condition makes him unable to understand the proceedings, or that he is unable to help in his defense, he is found incompetent. The competency evaluation, as determined in Dusky v. United States, is whether the accused "has sufficient present ability to consult with his lawyer with a reasonable degree of rational understanding—and whether he has a rational as well as factual understanding of the proceedings against him." Being determined incompetent is substantially different from undertaking an insanity defense; competence regards the defendant's state of mind at the time of the trial, while insanity regards his state of mind at the time of the crime. It has also been referred to as a "730 exam".

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