LOS ANGELES (CBS) — A deputy district attorney wept before a jury Tuesday as she admitted she consumed three glasses of wine and several shots of tequila at a bar before getting behind the wheel of her car and rear-ending a vehicle in Long Beach last year.

"I can't believe I did this," Marilyn Seymour told the Los Angeles Superior Court jury hearing the civil case brought by 21-year-old Chelsea Ann Caughran and Jocelyn Hernandez, both of Long Beach.

"I'm sorry," she said. "I feel so ashamed for putting people through this. There's no excuse for it."

Seymour said she initially was not satisfied with classes she took on alcohol-education after the crash. But she said she eventually listened to other people at the meetings "and realized what an idiot I was" the night she caused the accident.

Seymour has admitted liability in the case. The plaintiffs maintain she had a blood-alcohol level of .26 -- more than three times the legal limit of .08 in which a person is considered too intoxicated to drive.

The trial is to determine any award of money owed the plaintiffs, including any possible punitive damages.

The accident occurred about midnight on April 2, 2010, on Pacific Coast Highway. Attorneys for the plaintiffs maintain Seymour was driving about 70 mph at the time of the collision, but Seymour told jurors she was going within the speed limit, about 40 to 45 mph.

In his opening statement, Seymour's lawyer, Albert Di Rocco, said that while his client is obligated to pay some money -- the two women claim back pain and other injuries -- the as-yet publicly undisclosed amount requested by their lawyers is excessive.

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