Marin County Deputy Killed in Double Homicide - NBC Bay Area

Marin County Deputy Killed in Double Homicide

Deputy was at home trying to counsel family about how to deal with threats by ex-boyfriend



    Marin County Sheriff's Deputy Jim Mathiesen is dead after being shot while trying to help a friend. Investigators say Mathiesen was off duty when he encountered parolee Thomas Halloran armed with a gun. NBC Bay Area's Cheryl Hurd reports. (Published Wednesday, July 20, 2011)

    The bodies of a Marin County Sheriff's deputy and another man, who was allegedly harassing his ex-girlfriend, were found in a rural home in Petaluma.

    The deputy was identified as 49-year-old Jim Mathiesen. He had been shot and pronounced dead at the scene, according to police reports.

    At 12:12 a.m., authorities received a call that shots had been fired in the 800 Block of Liberty Rd. in Petaluma.

    While en route to respond to the report, authorities said they were told that 28-year-old Thomas Edwin Halloran had taken a hostage at gunpoint and there had been at least one shot.

    Moments later, authorities were informed that Halloran had been shot by someone in the house.

    The Sonoma County Sheriff's Office said that Halloran was involved in a relationship with a woman who lived at the address of the shooting but it had recently ended.

    Halloran allegedly had made numerous threats against the woman and her family, including death threats, according to reports. 

    The woman and her family were close friends with Mathiesen, seen on the right, and had reportedly asked him for his advice on how to deal with the situation.

    Mathiesen arrived at the family's home sometime before midnight to offer his advice on how to handle Halloran. 

    About 20 minutes later Halloran reportedly walked onto the family's property. The family said they  asked Halloran to leave and that's when he shot Mathiesen twice in the upper body.  Mathiesen was unarmed at the time.

    Halloran, seen below, then reportedly took someone in the house hostage and held her at gunpoint demanding that his ex-girlfriend come forward. 

    Thomas Edwin HalloranHe then allegedly forced the hostage outside and into a garage while threatening to shoot her.  While Halloran was attempting to force the hostage into a vehicle at gunpoint, a third unnamed resident of the house grabbed a gun  and shot Halloran, killing him.

    Halloran was shot twice, once in the upper body and once in the lower body.  The hostage and other residents were not injured. 

    Detectives discovered that Halloran was on active state parole for making terrorist threats in the past and had numerous arrests in both Marin and Sonoma Counties. 

    A memorial service is now be being planned for the deputy.

    "This is tragic news, Jim died trying to help others. He was known for his kindness and his helpful nature." Sheriff Bob Doyle said.