On June 6, 1998, Alvarez fired an SKS assault rifle at a group of people at an apartment complex. Alvarez suspected that some of the group were members of a rival gang. Two of the codefendants fired handguns. Although ballistics test determined that Alvarez did not fire the fatal bullets, testimony revealed he helped plan the drive-by shooting and supplied one of the cars used. Two people (who were brothers) were killed and six were injured by gunfire.
On June 17, 1998, Alvarez shot and killed two young men with shotguns in an apartment complex in Southwest Houston. The victims were shot at close range in the back and face. In this shooting, Alvarez supplied the shotgun and the same SKS assault rifle. Alvarez was identified at trial as the shooter.
Officers found the shotgun and the SKS assault rifle in his closet. Testimony showed that none of the four victims in these incidents were members of the rival gang.
Evidence presented at the punishment phase of the trial showed that Alvarez shot and killed a man in an apparent random attack on May 30, 1998, as the victim was driving home.