A conviction in a misdemeanor DWI case is reversed as defense counsel's behavior, considered as a whole, constructively denied appellant his Sixth Amendment right to the effective assistance of counsel. Defense counsel, although physically present in the courtroom at all the requisite times, effectively boycotted the trial proceedings and entirely failed to subject the prosecution's case to meaningful adversarial testing. In so doing, he abandoned his role as advocate for the defense and caused the trial to lose its character as a confrontation between adversaries, and prejudice to the defense is legally presumed.