The CCA recently considered this issue in Woodall v. State. I say they “considered" it – actually the Court was careful not to provide a definite holding on the matter. Instead, it punted the case on procedural (waiver) grounds. Nonetheless, the CCA did provide some dicta that is a helpful insight into its thinking.
We believe that, under the facts of this case, memory loss did not render [the witness] “absent” for Confrontation Clause purposes…The Supreme Court has generally rejected the notion that a present and testifying witness is nevertheless absent for confrontation purposes if the witness suffer from memory loss.Curiously, the CCA cites only pre-Crawford cases. For example, citing a 1970 Supreme Court case, the CCA quoted the concurring opinion of Justice Harlan, in which he opined that
a witness’s lack of memory should have no Sixth Amendment Consequence.However, the legal landscape has drastically changed since the time of Justice Harlan’s opinion. I doubt Scalia would agree with such reasoning today. Then again, as a strict constructionist, maybe he would. If the witness is available at trial, even if she cannot remember anything, is that enough to satisfy the 6th Amendment? I would argue NO, but perhaps I’m wrong. Either way, we will not find out with the Woodall case, because the CCA passed on the ultimate issue.