Goulet was convicted of carrying a gun without a concealed weapon permit and invasion of personal privacy. After violating his probation, Goulet was sentenced to two years in jail.
After his release, Goulet moved to Berkeley, where until last fall, a neighbor said the twin brothers lived for at least a year in a brown-shingled house on a quiet street.
Alicia Morrison said she and her husband lived in the apartment just below the brothers and called the police in September when they got into a violent fight.
"I didn't think it was an everyday fight. It sounded like one of them was going to get killed," she said. "They would throw each other down on the ground and they had two dogs upstairs who sounded like they were really scared."
She said Jeremy left before the police arrived on that occasion.
She said neighbors had called police for the same reason before, and a few days after Morrison called the police she said they came by the apartment again because Jeremy Goulet's girlfriend had been screaming.
"Every time the police were called they acted like it was no big deal," she said.
Jeremy Goulet had recently moved to Santa Cruz and taken a job at a harbor cafe, attempting to start over, his father said.
About 75 miles south of San Francisco, Santa Cruz is known for its world-class surf spots, historic downtown with bookstores and coffee shops, and the University of California, Santa Cruz. Its boardwalk is a major summer draw for tourists hoping to escape inland heat or enjoy a classic California experience.
Lately, the city of 60,000 people had seen a spike in assaults that community leaders had planned to address during a downtown rally.
Meanwhile, hundreds of grieving community members gathered for a vigil near the police department Wednesday evening.
The photos of Baker and Butler sat perched on a table surrounded by a cluster of flowers and candles that grew throughout the evening, while at other tables, people wrote notes to the officers' families, and children drew cartoon hearts and daisies on a banner in their honor.
Some who attended the vigil wore blue and black armbands in solidarity with the police officers attending.
Jeffery Goulet, the suspect's twin brother, released a statement Wednesday saying his family was deeply saddened.
"We would also like to extend our deepest sympathies to the families of Sgt. Loran Baker and Detective Elizabeth Butler," it said.
Baker was a 28-year veteran of the force whose son, Adam Baker, served as a community service officer. Butler, a 10-year veteran of the force, came to Santa Cruz to study at the university and stayed.
Associated Press writers John S. Marshall in San Francisco, Lisa Leff in Oakland, California, and Nigel Duara in Portland, Ore., contributed to this report.
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