Ming Qu, Ying Wu.

USC engineering students Ming Qu, left, and Ying Wu were shot to death in April 2012. Bryan Barnes, one of two men charged with the fatal shootings of the two Chinese graduate students, pleaded guilty Wednesday to two counts of first-degree murder. (Los Angeles Police Department)

The fathers of two USC graduate students who were shot to death in April 2012 stood before a judge Wednesday and asked for the most severe penalty for their children's killer, whom they described as a "ruthless murderer" and "cold-blooded criminal."

"In China, where I come from, it is only a matter of course that a killer pays a life for a life," XiYong Wu said.

But Bryan Barnes, 21, escaped the death penalty by agreeing to plead guilty to two counts of first-degree murder with special circumstances in exchange for two consecutive life terms in prison without the possibility of parole.

His guilty plea came before a trial in the slayings of Ying Wu and Ming Qu, 23-year-old USC engineering students from China who were killed while sitting in a parked BMW about a mile west of campus.

Barnes' co-defendant, 21-year-old Javier Bolden, is still awaiting trial. Because of the special circumstance allegations of multiple murders and murder in the commission of a robbery, prosecutors could have sought capital punishment in the killings.

The slayings rocked the USC community and drew media attention in the victims' native China.

Los Angeles County Superior Court Judge Stephen A. Marcus told the victims' parents that he was deeply sorry for their loss, calling the killings a horrific tragedy.

The fathers, Wanzhi Qu and XiYong Wu, addressed the court and said the killings devastated their families.

"The vicious murderer you see here in court took away her life, but also shattered the dreams and hope of our entire family into pieces and pushed us into the abyss of endless pain," Wu said, adding that his family had waited "two long years" for justice for their "angel."

Qu said his son, a straight-A student, "came with beautiful dreams, but died tragically at USC."

"This ruthless murderer took his precious life, killed his dreams together with our hopes," Qu said.

Nine days before he died, his son told him the couple were in love, Qu said.

Addressing Barnes, he added, "Our children left us and [you] took our heart and soul away.… You devastated our lives. You deserve the death penalty."

Barnes and Bolden were arrested in 2012 after Los Angeles police detectives were able to connect Wu's stolen black iPhone to the suspected gunmen.

During a weeklong preliminary hearing last year, prosecutors said investigators used the GPS in Wu's phone to track down its whereabouts and that led to Barnes. Detectives got a court order to eavesdrop on Barnes' telephone conversations. In one, he allegedly talked to Bolden, casually describing his attempt to sell the phone that prosecutors believe was Wu's, according to testimony during the preliminary hearing.

Barnes said he hoped to unlock the phone to give to Bolden as a birthday present. Instead, he sold it to a mobile store for $230, according to a transcript of the call. At one point in the conversation, Barnes described an incident in which he and Bolden "ran up on them little Asian people" and alluded to shooting the phone's owner.

Barnes' former girlfriend testified that he admitted stealing the phone. She also testified that Barnes told her he "might've shot somebody" in the process. In addition to the USC slayings, investigators said they were able to link Barnes and Bolden to another shooting. Deputy Dist. Atty. Daniel Akemon asked the court Wednesday to dismiss that unrelated attempted murder charge against Barnes.

Bolden is due in court March 21. Prosecutors have not yet decided whether to seek the death penalty.

richard.winton@latimes.com