Guizar

A jury convicted appellant Pedro Mata Guizar of first degree murder (Pen. Code, § 187); it also found that he had used a firearm (§ 12022.5) and inflicted great bodily injury (§ 1203.075) in the commission of this offense. The trial court sentenced Guizar to a term of 27 years to life in state prison. He appeals, contending that his conviction is the result of ineffective assistance of counsel. We reverse the conviction because the jury heard highly prejudicial, inadmissible evidence of Guizar’s alleged criminal history.

I. Facts

At approximately 9:30 p.m. on the evening of October 19-20, 1983, victim Pedro Aguilar went with his nephew Juan Cerda Viruela to Danny’s Tavern in East Palo Alto. Aguilar was already “tipsy,” but he ordered more drinks at the bar. Neither Viruela nor Aguilar knew appellant Pedro Mata Guizar, who was at the bar when they arrived. Guizar also consumed much alcohol that night.

Aguilar, Viruela, and Guizar all gambled on a dice game at some point in the evening. Aguilar began losing and accused another player, Leonel Zaragoza, of cheating. The two exchanged words, then began exchanging blows. Defense witnesses testified that Aguilar grabbed…