Art. 38.08. DEFENDANT MAY TESTIFY.  Any defendant in a criminal action shall be permitted to testify in his own behalf therein, but the failure of any defendant to so testify shall not be taken as a circumstance against him, nor shall the same be alluded to or commented on by counsel in the cause.
Acts 1965, 59th Leg., vol. 2, p. 317, ch. 722.