PETALUMA (CBS SF) – Marin County Sheriff Robert Doyle paid tribute Tuesday afternoon to Deputy Jim Mathiesen, who was fatally shot early Tuesday by a friend’s ex-boyfriend near Petaluma.
The ex-boyfriend, Thomas Edwin Halloran, 28, of Marin County, was in turn killed by a man who lived at the residence in the 800 block of Liberty Road in Sonoma County where the fatal shootings occurred.
“This is tragic news. Jim died trying to help others,” Doyle said.
“He was known for his kindness and his helpful nature.”
Mathiesen, 49, of Petaluma, worked as a sheriff’s deputy for nine years. He was assigned to the custodial division that includes the county jail and Marin County Superior Court.
KCBS’ Bob Melrose Reports:
Mathiesen was a close family friend of the woman who had been dating Halloran since March, Assistant Sonoma County Sheriff Lorenzo Duenas said.
When the woman broke off the relationship nine days ago, Halloran made numerous threats to the woman and her family, including one made earlier Monday night, Duenas said.
The woman and her family asked for Mathiesen’s advice and help because he was employed as a sheriff’s deputy, and Mathiesen arrived at the Liberty Road residence between 11:30 p.m. and 11:50 p.m. Monday, Sonoma County sheriff’s Sgt. Carlos Basurto said.
Halloran showed up at the property about 20 minutes after Mathiesen arrived, and Mathiesen went outside to ask Halloran to leave, he said.
Mathiesen was unarmed when Halloran shot him twice in the upper body.
Halloran then found a woman inside the house and threatened to shoot her if he did not locate his ex-girlfriend. He then forced the woman at gunpoint into a garage and threatened to shoot her, Basurto said.
While Halloran was trying to force the woman into a vehicle, a male resident of the house shot Halloran once in the upper body and once in the lower body, he said.
Halloran and Mathiesen died at the scene. All the weapons were recovered.
Halloran was on active parole for making terrorist threats in the past and had numerous arrests in Marin and Sonoma counties.
Halloran also has possible gang and prison affiliations. On July 23, 2008, Petaluma police arrested Halloran for allegedly vandalizing his ex-girlfriend’s car and sending her death threats via text messages.
Halloran, a Novato resident at the time, allegedly vandalized the car on July 21 and evaded arrest for two days.
The Marin County Sheriff’s Office found Halloran and turned him over to Petaluma police. Halloran was booked at Sonoma County Jail for stalking, criminal threats, felony vandalism and violating probation.
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