A jury found appellant, Moses Johnson, guilty of murdering his wife, Evelyn Johnson. Tex. Penal Code Ann. Â§ 19.02 (Vernon 2003). The jury sentenced appellant to forty-five years confinement in the Institutional Division of the Texas Department of Criminal Justice. In three issues, appellant challenges his conviction, arguing that (1) he was denied the right to a unanimous jury verdict, (2) the trial court erred when it excluded appellants expert witness during the punishment phase of the trial, and (3) he was denied effective assistance of counsel. We affirm.