Tanzi: Counsel not ineffective in failing to present evidence of XYY abnormality

In Tanzi v. Sec., Fla. Dep’t of Corrections, No. 13-12421 (Nov. 19, 2014), the Court affirmed the denial of habeas relief to a Florida inmate sentenced to death for a murder committed in 2000. The Court rejected the argument that counsel was ineffective in failing, among other things, to present evidence of Tanzi’s XYY abnormality. The Court noted that men with XYY chromosones tend to have diminished socialization skills, but do not automatically become antisocial. The Court also noted a defense mental expert’s testimony that knowledge that Tanzi had an extra & chromosome would not have changed any of the opinions he expressed during the penalty phase. Tanzi therefore failed to satisfy the prejudice prong of Strickland’s ineffective assistance of counsel standard.