Graham, Wash. – Over the weekend, Washington State Patrol (WSP) Troopers responded to a serious injury collision in Graham, Washington, which resulted in the arrest of Chadwick Dickerson, an off-duty Major with the Pierce County Sheriff’s Office (PCSO).
On July 12, 2025, around 3:46 pm, Dickerson was off-duty and driving his personally owned black Dodge Ram truck northbound on 132nd Avenue East approaching the intersection at 288th Street East. As Dickerson entered the intersection, he collided with a white Ford Expedition that was driving west on 288th Street East. As a result of the collision, the Expedition rolled onto its passenger side, coming to rest in a ditch on the northwest corner of the intersection. Dickerson’s truck came to rest in the same ditch after the collision.
The collision occurred in unincorporated Pierce County, and as such, PCSO was dispatched to investigate. Pierce County Sheriff deputies were dispatched and arrived on the scene around 4:26 pm. To avoid a potential conflict of interest, after identifying the involvement of a member of their agency, PCSO requested WSP respond to handle the collision investigation at approximately 4:43 pm. Additionally, WSP was advised that all occupants of the Expedition were being transported by fire to local area hospitals as a precaution, and that Dickerson was taken to a local urgent care facility by a family member who contacted the scene after the collision. As a result, WSP Troopers were dispatched to both the collision scene and the urgent care to contact Dickerson.
Troopers arrived at the collision scene around 5:15 pm. They observed that all involved parties had been transported away from the scene for medical treatment, and all associated debris from the collision had been cleared out of the roadway. The remaining scene consisted of the two vehicles involved resting in the ditch, with the Expedition still resting on its passenger side. Deputies on scene provided information about the collision’s occurrence, including the identity of the causing driver and his association with PCSO. Troopers were also provided with information about the six occupants of the victim vehicle, the Expedition, which included a pregnant 27-year-old female driver, her 30-year-old husband, her 57-year-old mother, and her three children, ages 8, 4, and 3.
The scene was carefully documented by troopers, after which the vehicles were towed and the on scene investigation was complete at that time. www.wsp.wa.gov