Man, 21, Convicted in Fatal Shooting of Security Guard at Mall

A 21-year-old man was convicted of first-degree murder on Friday for shooting a Sears security guard to death at the Mall of Orange last year.

Gilbert Acosta now faces a minimum of 25 years to life in prison for the murder of Kyle S. O’Brien, who was a prominent student leader and athlete at Cal State Fullerton.

The victim was working on Aug. 15, 1997, when Acosta tried to get a cash refund for a paint sprayer. A clerk got suspicious because Acosta did not have a receipt for the $152 item and alerted security guards.

The shooting occurred when O’Brien and another security guard, Randall DePue, accompanied Acosta to his car, where he was supposed to produce identification. O’Brien was shot twice in the chest, and DePue was hit once in the arm.

O’Brien was 22 years old and about to start his senior year when he was killed. He was captain of the school’s fencing team and vice president of finance in student government.

His family filled several rows of the courtroom on Friday and later said they were satisfied with the verdict.

“There is no joy in our hearts at a verdict being rendered nor does anything about this case begin to make up for the tragic loss of our son,” O’Brien’s parents said in a prepared statement. “What this is about, what this has always been about, is justice. Justice that a murderer will be punished for his crime.”

Acosta’s father, Alfonso, said outside court that his son was unjustly convicted.

“He’s not a killer, that’s all I can say,” the father said with tears in his eyes. “My son is not a killer.”

The jury did not convict the defendant of the special circumstance allegations of murder during the course of a burglary and a robbery--charges that could have resulted in a sentence of life in prison without parole.

Deputy Public Defender Ronald Klar, who represented Acosta, said he was pleased despite the guilty verdict because his client was not convicted of the special circumstance charges. Klar had contended during the trial that Acosta’s gun went off during a struggle with the two guards and that his client had not intended to shoot anyone.

But Deputy Dist. Atty. Lew Rosenblum, in his closing arguments this week, said Acosta was a drug addict who made his living by stealing.

“There is no defense to what he did,” Rosenblum told the jury. “The best he can come up with is it’s an accident. Four times the gun goes off in an accident? No.”