• Preserve vehicle condition, event-data-recorder and telematics evidence.
• Collect law-enforcement, 911, body-camera, dash-camera and dispatch records.
• Identify roadway, signal, surveillance and witness evidence.
• Send targeted preservation notices to relevant vehicle owners, employers, insurers, repair facilities and digital-data custodians.

Migration source: https://www.victimsguide.com/az-crash-investigation-evidence. Verify current Arizona primary authority before reliance.