Throughout history, mental health has played an important role in the legal system, particularly in relation to issues of competency and health mental. Questions regarding competency to stand trial have developed throughout history and cover a wide range of topics, including: predictor variables, malingering, mental retardation, standards of competency for execution, and validity of competency assessments. The question of jurisdiction in legal proceedings is anchored in English Common Law as early as the 17th century (CITE-ALawPsych&pol). Common law states that the standard of fitness to stand trial requires that the accused understand the proceedings against him and be able to assist in his defense (Cite-lackinsight). William Blackstone alluded to fitness to stand trial in his Commentaries on the Laws of England (1783), which questioned the abilities of mentally defective defendants, then considered "insane", to plead with the "caution that 'he should' (CITE-). A defendant's failure to exercise due care violates his or her right to a fair trial because he or she cannot make the decisions necessary to mount a defense. Although jurisdiction was recognized early on as an important pretrial issue, a legal standard for jurisdiction was not established until 1960 in Dusky v. UNITED STATES. The decision resulting from Dusky v. United States (1960) gave rise to the "Dusky standard", which aims to prevent an unfair trial by allowing a defendant to be considered incompetent if he or she does not meet competency standards. Once found incompetent to stand trial, the defendant may be restored to competency and then returned to court for trial. Many variables determine whether a certain... middle of paper ......ts with a clinical diagnosis of psychosis were found incompetent to stand trial, compared to only 9 percent of those diagnosed as non-psychotic. A diagnosis of incompetence is correlated with a major psychotic and non-psychotic disorder, while a diagnosis of a minor non-psychotic disorder or an alcohol/drug disorder is correlated with a finding of competence (#8). Clinical variables are of the utmost importance in a competency assessment. Individuals scoring lower on IQ measures of mental functioning are more likely to be considered IST than those functioning at a higher rate. Additionally, the diagnosis of a mental illness, particularly one with symptoms of psychosis and major non-psychotic disorder, tends to be correlated with an EIS decision. Conversely, defendants diagnosed with minor drug, alcohol, or non-psychotic disorders are more likely to be found CST..