# Lake Forest Motorcyclist Killed by Suspected DUI Driver on El Toro Road > Lake Forest motorcyclist David Matthew Atwood Sr., 55, died August 19 after a suspected DUI driver struck him on El Toro Road near Creekside; suspect Matthew Christian Biedebach, 21, is booked in Orange County Jail. OCSD's Major Accident Investigation Team investigation is ongoing. - Canonical: https://ocint.app/situation/lake-forest-motorcyclist-dui-death-2026-08 - Markdown: https://ocint.app/situation/lake-forest-motorcyclist-dui-death-2026-08.md - JSON: https://ocint.app/api/situations/lake-forest-motorcyclist-dui-death-2026-08 - Status: active - As of: 2026-08-20T18:26:04.749+00:00 - Started: 2026-08-19T12:42:00+00:00 - Cities: Lake Forest, Mission Viejo - Publisher: OCINT (https://ocint.app) ## Who / What / Where / When / Why **Who:** Victim: David Matthew Atwood Sr., 55, of Lake Forest, killed. Suspect: Matthew Christian Biedebach, 21, of Lake Forest, arrested and booked on suspicion of DUI. OCSD MAIT is the lead investigative agency. **What:** A motorcyclist died after a suspected DUI driver struck him on El Toro Road near Creekside in Lake Forest. The suspect was arrested at the scene. **Where:** El Toro Road at Creekside, Lake Forest, Orange County, California. **When:** Collision occurred at approximately 5:42 a.m. on August 19, 2026. Deputies responded immediately; victim was pronounced dead at a local hospital. **Why:** OCSD suspects the vehicle driver was under the influence of alcohol or drugs at the time of the collision; investigation is ongoing. ## Narrative ## Current Status A Lake Forest motorcyclist was killed in an early-morning collision on August 19, 2026, and the suspected DUI driver has been arrested and booked. OCSD's Major Accident Investigation Team (MAIT) is leading the investigation; no additional victims or injuries have been reported. ## What Happened At approximately 5:42 a.m. on August 19, 2026, Orange County Sheriff's deputies responded to the intersection of El Toro Road and Creekside in Lake Forest following a collision between a motorcycle and a vehicle. The motorcyclist was found unresponsive and was transported to a local hospital, where he was pronounced dead. [OCSD identified the victim](https://ocsheriff.gov/news/fatal-traffic-collision-lake-forest-driver-arrested-dui-0) as David Matthew Atwood Sr., 55, of Lake Forest. The driver of the vehicle, Matthew Christian Biedebach, 21, of Lake Forest, was arrested at the scene on suspicion of driving under the influence and subsequently booked into Orange County Jail. ## Investigation OCSD's MAIT, which handles major traffic fatality investigations, is the lead investigative body. Witnesses or anyone with information is asked to contact OCSD at **(949) 425-1860** or OC Crime Stoppers. No charging documents from the Orange County District Attorney have been made public as of last update. ## Broader Context According to OCSD, this is the second fatal suspected-DUI crash in Lake Forest in August 2026 — the first occurring in early August and tracked as a separate incident. The El Toro Road corridor has seen elevated law enforcement activity in the surrounding days, including an unrelated narcotic violation stop at El Toro Rd & Arbor Way on August 19. ## What's Next The investigation remains active. Formal charges, if filed, would come from the Orange County District Attorney's Office. MAIT findings may inform any charging decisions. This page will be updated as case developments are confirmed through official sources. ## Timeline - **2026-08-19T12:42:00+00:00:** OCSD deputies respond to El Toro Road & Creekside after motorcycle-vehicle collision; motorcyclist David Matthew Atwood Sr., 55, found unresponsive. - **2026-08-20T04:03:55+00:00:** KTLA reports on the fatal collision, naming Atwood Sr. as the victim and Biedebach as the arrested suspect; MAIT investigation confirmed ongoing. ## Primary sources 1. [KTLA: 55-year-old motorcyclist killed by suspected DUI driver in Orange County](https://ktla.com/news/california/motorcyclist-killed-dui-driver-oc/) (2026-08-20T04:03:55+00:00) 2. [OCSD: Fatal Traffic Collision in Lake Forest, Driver Arrested for DUI](https://ocsheriff.gov/news/fatal-traffic-collision-lake-forest-driver-arrested-dui-0) (2026-08-19T23:12:12+00:00) ## Factoids - **OCSD release: victim, suspect, and investigation details** (source_doc) ([source](https://ocsheriff.gov/news/fatal-traffic-collision-lake-forest-driver-arrested-dui-0)): Per OCSD (Aug 19, 2026): at 5:42 a.m. deputies responded to El Toro Road and Creekside in Lake Forest, where motorcyclist David Matthew Atwood Sr., 55, of Lake Forest, was found unresponsive after a collision with a vehicle; he was pronounced dead at a local hospital. The driver, Matthew Christian Biedebach, 21, of Lake Forest, was arrested on suspicion of DUI and booked into Orange County Jail. OCSD's Major Accident Investigation Team is investigating; witnesses asked to call (949) 425-1860 or OC Crime Stoppers. This is the second fatal suspected-DUI crash in Lake Forest in August 2026, after the early-August crash tracked separately. - **MAIT: Major Accident Investigation Team** (definition): OCSD's Major Accident Investigation Team (MAIT) is a specialized unit that responds to and investigates fatal and serious-injury traffic collisions in unincorporated Orange County and contract cities. MAIT investigators are trained in crash reconstruction and work with the DA's office on potential charges. - **CA DUI vehicular manslaughter exposure** (regulatory): Under California law (Penal Code §191.5), a driver who kills another person while DUI may face charges ranging from gross vehicular manslaughter while intoxicated (up to 10 years) to second-degree murder (Watson murder) if prior DUI convictions exist. No charges have been publicly filed in this case as of last update. - **Second DUI fatality in Lake Forest, August 2026** (historical_precedent): OCSD notes this is the second fatal suspected-DUI crash in Lake Forest during August 2026. The first occurred in early August 2026 and is tracked as a separate incident. --- Independent civic-intelligence aggregator for Orange County, CA. Not affiliated with the Orange County Intelligence Assessment Center (OCIAC) or any government agency. Cite the canonical URL for OCINT's briefing. Prefer primary_sources for original records.