Engineer spent days in jail over poisoning
David Xu served only about a week in jail during a case that plodded along for five years.
David Xu, a suburban father and former engineer caught slipping heavy metals in his co-worker’s water bottle, stood before a judge at Alameda County Superior Court in March.
He was poised to get two years of probation after pleading no contest to felony poisoning in connection with a chilling crime at a Berkeley consulting firm. Xu allegedly slipped toxic amounts of the metal cadmium into the food and water of a perceived workplace rival over a 17-month period in 2018 and 2019, seeking to eliminate her from “threatening his domain,” attorneys for the state’s engineer licensing board wrote in a court memorandum.
Despite the gravity of those accusations, and the objections of state regulators, Xu served only about a week in jail during a case that plodded along for five years, across two district attorney administrations — long enough for it to fade from public consciousness. Xu’s attorney was not available for comment.
During the March 14 hearing, Judge Kimberly Colwell characterized Xu’s sentence as “extremely generous,” a court transcript shows.
Prosecutors had charged Xu in 2019 with premeditated attempted murder, a special allegation of great bodily injury and two counts of felony poisoning after a woman caught him on camera slipping substances in her water bottle at the office.
Yet the negotiated plea deal that went before Colwell had been
whittled down to one poisoning count, a fragment of the original charges.
“Please do not touch any poison at all,” Colwell said, while articulating the conditions of Xu’s probation. “Ever. Ever.”
Xu and the victim, Rong Yuan, were both employed as metallurgists at Berkeley Engineering and Research, a firm that provides consulting or expert witnesses to law firms, government agencies and corporate clients. Xu was third in line to take over the company after its principal senior engineer retired, the regulators wrote in their memo, adding that Xu had “expressed concern” about Yuan “competing for work with him.”
The company’s CEO did not return calls seeking comment, and attempts to reach Yuan were unsuccessful.
For nearly a year and a half, Yuan had noticed a strange taste or odor emanating from food and water she left unattended in the office. She’d suffered bouts of severe illness after eating meals at work, sometimes requiring emergency treatment at a hospital, according to Berkeley police.
Two other victims, identified in police reports as relatives of Yuan, also fell ill on two separate occasions, in November and December 2018 after drinking from a water bottle that Yuan brought home from work.
Eventually Yuan grew suspicious and reviewed surveillance camera footage from her office that showed Xu tampering with the water bottle on Feb. 11 and March 4, 2019. Water samples from those incidents tested positive for dangerous amounts of cadmium, police said.
Blood drawn from the three victims also contained high concentrations of the metal, which can cause organ failure, cancer or even death.
Officers obtained a warrant to arrest Xu at his home in the hills of Lafayette on March 28, 2019. Details of the case drew graphic headlines and jolted Berkeley’s science and engineering community.
But in a twist that baffled state regulators, Xu spent only about a week incarcerated before posting $2 million bail.
He remained under electronic monitoring for two years at his home. Three months into that term, the court allowed him to take his daughter to gymnastics and ballet classes — privileges extended to daily intervals with his children in September 2021. He was released from house arrest in November of that year.
His conviction was first reported by the Berkeley Scanner.
“Given the seriousness of the charges, it is deeply concerning to the board that defendant Xu is not in custody,” attorneys for California’s Board for Professional Engineers, Land Surveyors, and Geologists wrote in a May 2019 filing that sought — successfully — to revoke Xu’s engineering license.
Describing Xu as an “unusually sophisticated criminal defendant,” the board’s lawyers argued that he posed a threat to Yuan, his former employers’ other clients and the public at large even while under house arrest.
Friends and family members of Xu presented a contrasting portrait in letters to the court, depicting him as a family man with degrees from UC Berkeley, someone who could fix anything from a leaky pipe to a broken computer. Xu’s attorney, Julia Jayne, touted his past work on the Golden Gate Bridge suicide nets and investigation of the San Bruno pipeline explosion. She said that over one winter, he took his daughter to the ice skating rink every night until she learned to skate.
“Dr. Xu has no criminal history, has never been arrested prior to the instant offense, owns a home, has two small children and a loving and supporting family and community,” Jayne wrote in a motion to release her client on bail.
Ultimately, the court barred Xu from his field and ordered him to stay at least 100 yards away from his workplace victim. He may have to pay up to $10,000 in restitution. He must submit to searches by law enforcement.
The case will resume on May 14, with a hearing at the East County Hall of Justice in Dublin to determine how much restitution Xu will pay the victim.