The Sixth Amendment's guarantee of a fair trial requires that a trier of fact's verdict in a criminal case be based upon evidence introduced or developed at trial. Can a trier of fact consider a non-identified and non-testifying defendant's in-court presence or demeanor as evidence of guilt?

Whether a trier of fact in a criminal case may consider a non-identified and non-testifying defendant's in-court presence or demeanor as evidence of guilt consistent with the Sixth Amendment's guarantee of a fair trial