After the Virginia Supreme Court remanded death row inmate Williams Burns' case to the circuit court for a hearing on whether he had mental retardation (and thus could not be executed), he became too psychotic to provide valid IQ test results.  The Circuit Court effectively sustained the Commonwealth's position that Burns had no right to be competent because the mental retardation hearing was not a criminal proceeding, and ruled that his failure to provide an IQ score required dismissal of his mental retardation claim. 

On appeal, the Virginia Supreme Court reversed, holding that the MR hearing was a criminal proceeding that required that Burns be competent.  The effect of the decision is to require that the circuit court determine whether Burns is competent, and if he is not, he may not be required to litigate the issue of mental retardation unless and until he is restored to competency.

Full opinion available here.