The Supreme Court of the United States barred the execution of intellectually disabled individuals in 2002. Soon the Court will address the standard that a State should use to determine whether an individual is intellectually disabled. There are ten states that use IQ scores to assess the intellectual competence of convicts, including Florida. Typically, in these states, a person with an IQ of 70 or higher is considered intellectually competent. Some psychologists maintain that using such a bright-line standard is scientifically outdated, and that IQ tests are not precise enough to make such a determination. The Court will hear arguments on the issue in Hall v. Florida, on March 3, 2014.
Read more here.