Double Slaying Recounted : Courts: Former Marine tearfully testifies that he remembers little from the night his ex-wife and daughter were killed.

A decorated former Marine wept on the witness stand Monday as he recounted the night he fatally shot his ex-wife and 5-year-old daughter--and wounded another woman--during a beer-soaked blackout two years ago.

Jeffrey Steven Gibson, 34, said he began to recall “bits and pieces” shortly after the May 29, 1993, shooting when he telephoned his mother to confess.

“I knew I had done something wrong,” he said.

“I said, ‘Mommy, I killed Tina.’ She said, ‘What about Amber?’ I said, ‘I don’t know. I think I killed her too.’ ”

Kristina (Tina) Gibson, 26, and her daughter Amber died in their San Clemente apartment from shots from a .45-caliber automatic pistol. Tina Gibson’s roommate, Wendy Johnson, was wounded in the chest during the attack, which took place 17 days after the Gibsons’ divorce became final.

Gibson’s account of the phone call to his mother from a Mission Viejo gas station capped a day of testimony during his murder trial in Orange County Superior Court.

Gibson, a former Camp Pendleton sergeant decorated for valor during the Persian Gulf War, faces up to life in prison without the possibility of parole if convicted of first-degree murder, because there was more than one death.

But his defense lawyer is seeking conviction on a lesser charge, such as second-degree murder, contending that the armed attack was an unplanned explosion of violence that may have been aggravated by Gibson’s hair-trigger military training and the emotional toll of growing up in an abusive family.

Gibson said he drank beer at an all-day keg party on the base on the day of the slayings and did not remember driving to the San Clemente apartment that Tina Gibson shared with Johnson and Amber.

Only later, Gibson said, did he recall what he did once he got there.

After shooting Johnson once, Gibson said he walked down the hall to Tina Gibson’s bedroom and found his ex-wife talking on the telephone.

“Tina was here looking at me. . . . I walked up to her and I remember shooting her in the chest,” Gibson said. “I shot one more time and looked to my left and everything turned white.”

The defendant said he aimed the gun at his own head, but had no memories until he arrived at the gas station, which is near two restaurants where Gibson said he used to have dinner with Tina Gibson and Amber.

In court Monday, Johnson and Tina Gibson’s parents showed little reaction as Gibson testified quietly, at times lowering his head almost out of view on the witness stand.

Defense attorney Stephen J. Biskar said outside the courtroom that Gibson’s personality was a “volatile mix,” a history of explosive temper and excessive drinking. Gibson’s ambush training, emphasizing split-second decisions on when to shoot, may also have played a part, said Biskar, a court-appointed attorney.

“The training kind of took over, particularly in shooting his daughter. He had no reason to do that,” Biskar said. “This was an emotional, irrational decision.”

Gibson spent much of the day matter-of-factly recounting the couple’s up-and-down marriage, which was buffeted by his extramarital affair and long absences for military training before it ended in divorce.

Even after the divorce became final, Gibson said he was seeking to repair the relationship. But Gibson said he feared he had damaged that effort by showing up at the home of Tina Gibson’s new boyfriend on the night before the murders. He said wanted to apologize the next day for invading his ex-wife’s privacy but could not remember when he decided to go there on the night of the murders.

Gibson and two aunts who testified portrayed a troubled life--from Gibson’s chronic bed-wetting as a youngster to the rocky marriage--that clashed with the spit-and-polish image of a decorated Marine.

Both aunts testified earlier in the day that Gibson wet his bed through adolescence and was mocked cruelly by a hard-drinking mother.

“It was a condition she would bring up often at parties and things, just to embarrass him,” said Carol Golik, his aunt from New York.

The aunts described Gibson as a “tempestuous” child who grew into a gung-ho Marine, serving in Saudi Arabia for more than three months before and during Operation Desert Storm. Gibson is expected to take the stand again today to face questioning by the prosecution.