A Fontana woman pleaded no contest Tuesday to charges stemming from a 2014 wrong-way, DUI crash on the 60 Freeway in Diamond Bar that killed six people, including her younger sister.

Olivia Carolee Culbreath pleaded no contest to six counts of second-degree murder during a court appearance at Clara Shortridge Foltz Criminal Justice Center in Los Angeles, according to an L.A. County District Attorney’s news release. Culbreath’s plea was not part of any negotiated plea bargain, and instead, she made an open plea to the court.

“She felt that it was important to spare her family, and the family of the victims, the trauma of a trial,” said Culbreath’s lawyer Robert Sheahen.

A no contest plea is viewed similar to a guilty plea, but it enables a defendant to avoid admitting guilt in a related civil lawsuit.

The change in plea comes as the parties in the case were preparing for trial. Jury selection was underway, and a panel of 75 jurors was in the courtroom Tuesday, Sheahen said.

Culbreath, now 25, is scheduled to be sentenced Sept. 7 in Department 108 of the Foltz Criminal Justice Center. She will be making a statement in court, Sheahen said.

Culbreath faces either 15 years or 30 years in a state prison depending on the evidence presented to the court at sentencing, according to Sheahen. The judge agreed to hear Culbreath and determine the sentence.

Sheahen said Culbreath, who was also injured in the crash, is a very responsible woman who made some terrible choices. She’s not some “wanton party girl,” he said.

Culbreath had given birth 11 days before the crash, according to Sheahen. He described her a single mother at home suffering from postpartum depression. She went out, and the evening ended in a horrific tragedy, he said.

“It was the aftermath of a very difficult childbirth, and she’s extremely remorseful,” Sheahen said.

On Feb. 9, 2014, Culbreath drove her red Chevrolet Camaro against traffic on the 57 and 60 freeways in Diamond Bar. She traveled north in the southbound lanes on the 57 Freeway and then headed east in the westbound lanes of the 60 Freeway at speeds of more than 100 miles per hour when she collided head-on with a Ford Explorer.

Another vehicle subsequently crashed into the Explorer.

During a preliminary hearing in January 2015, CHP investigators testified that witnesses saw Culbreath drinking at a Fullerton bar hours before the crash.

All four occupants of the Explorer were killed as were two passengers in the Camaro, including Culbreath’s sister Maya Culbreath, 24, of Rialto.

Culbreath had previously been convicted of driving under the influence on April 13, 2010, according to Department of Motor Vehicles records. She was stopped for two more violations before her license was reinstated in December 2011, according to the DMV, which lifted restrictions on her license just a week prior to the deadly crash.

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“She was warned by the court about the dangers of driving under the influence of alcohol and also was admonished that such future conduct could result in murder charges,” the release stated.

Culbreath had a .15 percent blood alcohol content — nearly twice the legal limit — about three hours after the crash.

Three generations of family members in the Explorer were killed: Huntington Park residents Gregorio Mejia-Martinez, 47; Leticia Ibarra, 42; their daughter, Jessica Mejia, 20; and her grandmother, Ester Delgado, 80.

The second passenger in Culbreath’s Camaro who died in the crash was her friend Kristin Young, 21, of Chino.

After the crash, Culbreath was initially hospitalized in a jail ward and then brought later to court on a stretcher. She has subsequently been brought to court in a wheelchair.

City News Service contributed to this report.