In Gonzales v. State (Tex. App.--Houston [1st Dist.] 1992), the police officer defendant shot and killed a woman whose car he chased after he and his co-officer passengers claimed she shot at their truck. Gonzales, 838 S.W.2d at 852.
The court held the trial judge erred in excluding evidence showing the deceased was the first aggressor.
The excluded evidence showed the deceased's prior violent acts, including a misdemeanor assault of police officers and a shooting of her ex-husband. Gonzales, 838 S.W.2d at 863.
Regarding harm, the court reasoned that:
(1) whether the deceased first fired at the defendant's truck was a hotly contested issue;
(2) the only significant evidence the jury heard of the deceased's violent character was her ex-husband's "naturally" suspect testimony that she was violent and quick-tempered. Id.
Thus, the court concluded the defendant was harmed. Gonzales, 838 S.W.2d at 864.