Knowledge and experience required for experts in atkins cases.

The United States Supreme Court's Atkins v. Virginia (2002) decision has created a need for experts who are knowledgeable and experienced in both mental retardation and forensic psychology. This article summarizes the issues that are critical to the diagnosis in the "close calls" that typify Atkins cases. A resolution of such close calls hinges upon the expert's ability to testify with regard to the characteristics of mild mental retardation and the way that diagnostic standards may be applied differently in clinical versus forensic settings. The critical impairments are not in the form of physical stigmata. They are characterized by difficulties in judgment when engaged in typical community functioning. The keys to these close calls are the individual's problems in functioning in the community with the degree of independence required for adults.