What is the legal test for reversal of a jury's verdict in a case of mistaken identity?

Where there is instructional error, our high court has held that reversal of the jury's guilty verdict is not required. "It is appropriate and constitutionally permissible to analyze instructional error with regard to an element of an offense by the harmless error standard of Chapman v. California (1967) 386 U.S. 18 . . . . [Citations.] This standard has been expressly applied to instructional error on the issue of whether a crime requires general or specific intent. [Citation.]" (People v. Brenner (1992) 5 Cal.App.4th 335, 339.)

"An instruction that omits a required definition of or misdescribes an element of an offense is harmless only if 'it appears "beyond a reasonable doubt that the error complained of did not contribute to the verdict obtained."' [Citation.] 'To say that an error did not contribute to the verdict is . . . to find that error unimportant in relation to everything else the jury considered on the issue in question, as revealed in the record.' [Citation.]" (People v. Mayfield (1997) 14 Cal.4th 668, 774.)