The day before Easter in 2016, Jon Warshawsky had lunch in La Jolla with his girlfriend, Amanda Walzer.

The next thing he remembers, he testified Wednesday, is waking up almost two months later in a La Mesa rehabilitation clinic. He could barely move his head or limbs.

He can’t recall that Easter Sunday, on March 27, when a woman who had been smoking marijuana crashed her car head on into his vintage Porsche, disabling him and killing Walzer.

“No, I don’t have any memory of that,” Warshawsky said in San Diego Superior Court, where he used an electric wheelchair, then a walker, to make his way slowly to the witness stand.

He was one of the first witnesses called in the trial of Hyun Jeong Choi, 36, who faces charges of second-degree murder, gross vehicular manslaughter and allegations of gross bodily injury and multiple victims related to the fatal crash.

Choi, who already had one DUI conviction, understood that she shouldn’t get behind the wheel of a car while impaired, a prosecutor said.

“She knew better,” Deputy District Attorney Andrew Aguilar told jurors in his opening trial statements.

“The defendant was high on marijuana, knew she was high on marijuana, knew that driving under the influence of alcohol or drugs was dangerous, yet she willingly chose to try to drive home,” Aguilar said.

He said Choi pleaded guilty to a 2012 DUI with a blood-alcohol content of .19 percent, well over twice the legal limit for drivers in California. The state has no laws setting a legal level for marijuana’s active ingredient, THC.

Choi’s attorney, Stephen Cline, told jurors that his client, who suffers from an anxiety disorder, had never before smoked the particular type of highly potent medical marijuana she bought about half an hour before the collision.

The drug “almost instantly kicked in” and Choi lost control of her arms and legs, Cline said.

“She was catastrophically impaired,” Cline acknowledged. “The issue is whether she is guilty of murder.”

The prosecutor, Aguilar, said Choi went to Mankind Cooperative dispensary in Miramar around 5 p.m. and bought two types of marijuana.

She drove about six miles, stopped to smoke some pot in her car, then continued east on Pomerado Road in Scripps Ranch.

Near Camino Alta, Choi lost control of her Toyota Corolla, swerved over a raised center median and plowed nearly head-on into Warshawsky’s westbound 1956 356A Speedster convertible.

Aguilar said the marijuana pipe in Choi’s car was still warm after the crash and she admitted to San Diego police that she was impaired by pot.

Walzer suffered major head and brain injuries.

Her mother, Marjorie Walzer, of Sherman Oaks, testified that she and her husband learned of their daughter’s crash early the next day, and drove to Scripps Memorial Hospital in La Jolla.

She said her daughter, an English professor at Fullerton College, underwent 11 hours of surgery.

“I thought that maybe with a lot of love and care, she was going to pull through,” her mother said. “After seeing her, we realized that was not the case.”

Her daughter was declared brain dead on March 29.

Warshawsky testified that before the crash, he was healthy and fit, working out in a gym four days a week. After the crash, with extensive rehab, he re-learned how to speak, eat and drink and to walk for short distances. He had surgery in May this year to re-align his damaged right eye.

The trial was to continue Thursday and is expected to conclude late next week.

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