For release on July 31, 2013

Matthew Braker, Deputy District Attorney
Homicide Unit
(408) 792-2531


A 47-year-old Gilroy woman was convicted this week of second-degree murder for the high-speed, rollover DUI crash that killed her own husband and daughter.

Stacy Lonnberg, who was highly intoxicated on a prescription pain medication mixed with more than half a dozen alcoholic drinks at the time of the crash, was found guilty Tuesday of two counts of murder after a two-week trial before the Hon. Ron Del Pozzo. The jury also found Lonnberg guilty of child endangerment. At the time of the crash, Lonnberg’s infant grandson was in a car seat in the back. He survived.

Lonnberg is scheduled to be sentenced on October 11, 2013. The maximum sentence is 36 years-to-life in prison.

“The use of a designated driver would have prevented the tragic murders of Fred Lonnberg and Tiffiny Gillette as well as the endangerment of Tiffiny’s infant,” prosecutor Matthew Braker said. “The victims’ family attended every day of the trial and learned that Defendant Lonnberg drove drunk hundreds of times in disregard of a warning from the court in 2005, and the safety of everyone else on the road.”

On the late afternoon of January 14, 2012, Lonnberg was driving a Toyota pickup truck northbound on Highway 85 near Los Gatos. Her 57-year-old husband, Frederic Lonnberg, her 26-year-old daughter Tiffiny Ann Gillette, and her daughter’s year-old son, were passengers as they traveled to a friend's wedding reception in Belmont. Witnesses said that Stacy Lonnberg was driving at more than 80 mph. One witness later told police that the truck was veering through the traffic lanes and going so fast that he said out loud: “This guy is suicidal.” That is when the truck sideswiped another vehicle, veered across the lanes, and flipped six times. The driver’s daughter, a hair stylist, was thrown from the truck and killed. The driver’s husband, a driver for UPS, was partially ejected, and died of his injuries in the hospital. The driver and her grandchild suffered only minor injuries.

The CHP officer noted that Lonnberg showed clear signs of intoxication after the accident and did not seem concerned for her husband or daughter, who lay dead on the highway. Expert testimony established that she had at least a .20 blood-alcohol level at the time of the accident, more than twice the legal limit. She also tested positive for Oxycodone. 


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