Not guilty plea for driver in crash that killed HFD veteran

David Mahon. (Courtesy photo/Special to West Hawaii Today)

A memorial centered by a photo of David Mahon and his 10-year-old son, Dylan, has been set up in memory of the Hawaii Fire Department veteran killed in a multiple-car crash May 22 on Mamalahoa Highway in North Kona. (Chelsea Jensen/West Hawaii Today)

Christopher Raymond Helmlinger turns to exit Kona Circuit Court Judge Melvin H. Fujino’s courtroom Thursday after pleading not guilty to manslaughter and second-degree negligent homicide charges. (Laura Ruminski/West Hawaii Today)

KEALAKEKUA — A Waimea man accused of manslaughter and negligent homicide in the traffic death of a Hawaii Fire Department veteran has pleaded not guilty to the charges stemming from the May 22 crash.