Appellant’s statements to the psychologist who evaluated his competency to stand trial were admissable to impeach his testimony about statements he had made to experts. Absent a waiver of the Fifth Amendment privilege, statements a defendant makes to experts appointed to determine his competency may not be used on the issue of guilt. However, the privilege cannot be construed to include the right to commit perjury. The trial court properly allowed the prosecution to impeach appellant’s testimony at trial with inconsistent statements he made to the examining psychologists. Further, even if it had been error to admit the statements, appellant was not prejudiced by the impeachment testimony because the other evidence of his guilt was overwhelming.