While police officers and insurance adjusters often automatically presume the trailing driver is at fault for following too closely (CVC § 21703), California law allows this presumption to be rebutted under the **Sudden Emergency Doctrine** or when the lead driver committed hazardous maneuvers.
1. Rebuttable Scenarios in Rear-End Crashes
| Collision Scenario | Lead Driver Violation | Legal Defense Doctrine |
|---|---|---|
| Reckless Cut-Off & Brake | Unsafe lane change without signaling (CVC § 22107) | Primary liability shifts to cutting vehicle. |
| Non-Functioning Brake Lights | Driving with defective safety equipment (CVC § 24603) | Comparative negligence applied to lead driver. |
| Sudden Reversing Vehicle | Backing on highway without reasonable safety (CVC § 22106) | 100% liability on reversing driver. |