LODI, Calif. -- A Lodi man with four drunken-driving arrests is facing murder charges after he allegedly ran over a 76-year-old woman last week, officials said.

Luis Hernandez, 21, is accused of being intoxicated while driving when he hit Violet Hill as she was outside getting her mail.

Hernandez, who suffered only minor injuries, was allegedly traveling 50 to 55 mph in a 35 mph zone, officials said.

During Cinco De Mayo weekend, the highway patrol arrested 78 people in San Joaquin County on suspicion of drunken driving, including Hernandez.

"Mr. Hernandez has a bench warrant from our court for a drunk driving that he didn't appear on. He has another drunk driving, it's almost too soon, he picked it up on May 1st," Deputy District Attorney Chuck Schultz said.

Hill's neighbor, Tim Maloney, who witnessed the accident, said Hernandez needs to be held responsible.

"It was murder, he was drinking. I mean he didn't know what he was doing because he was drunk, but you got to be held responsible."

A second-degree murder charge would mean a sentence of 15 years to life if Hernandez is convicted.