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Cowlitz County, WA Sheriffs Deputy Justin DeRosier


Justin DeRosier was born on January 28, 1990, in Kailua, Hawaii, to parents Neil and Kelly DeRosier. He attended Kelso public schools and graduated in 2008 from Kelso High School. Justin played sports as a child but was particularly fond of law enforcement. Everyone who knew him also knew that he would one day end up working in the law enforcement community. 


Upon graduating from high school, Justin went on to earn a criminal justice degree from Washington State University. While attending WSU, Justin was an intern at the Whitman County Sheriff’s Office and accepted a deputy position there in 2013.


After serving three years at Whitman County, Justin was sworn in as a Deputy Sheriff for the Cowlitz County Sheriff’s Office. 


On the evening hours of April 13, 2019, there were a number of reports called into the night shift law enforcement team at the Cowlitz County Sheriff’s Department. Deputy DeRosier was dispatched to checkout a poorly parked motor home that was partially blocking a narrow road near the Kalama River canyon. 


Shortly after arriving to the site, shots were fired and Deputy DeRosier radioed in that he had been hit. Several nearby law enforcement officers responded and arrived at the site where they were able to get Deputy DeRosier into a patrol car and bring him to safety. He was flown to PeaceHealth Medical Center in Vancouver and shortly after midnight on the morning of April 14, 2019, Sheriff’s Deputy Justin DeRosiersuccumbed to the gun shots. Sheriff’s Deputy DeRosierbecame the first deputy killed in the line of duty in the 165-year history of Cowlitz County. 


Sheriff’s Deputy DeRosier’s funeral service was held on April 24, 2019 at the University of Portland. He leaves behind his wife Katherine and infant daughter Lillian Naomi and is survived by his sister, Jenna and parents Neil and Kelly DeRosier.A

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