First things first: how fault really works in CA

California uses pure comparative negligence—each driver’s share of blame reduces their recovery (the court can split fault 0–100%). That rule comes from Li v. Yellow Cab Co. and the general duty to use ordinary care under Civil Code §1714. 

Tip: A traffic ticket helps, but it isn’t required. Fault flows from the facts and the law—including the Vehicle Code sections below.

The 10 most common crash types (and the code sections that decide fault)

1. Rear-end collisions (tailgating & brake-checking)
   
   • Drivers must not follow “more closely than is reasonable and prudent”: Veh. Code §21703.
   • Abruptly stopping without signaling (when there’s a chance to) is prohibited: §22109.
     Expect comparative fault arguments when both show up in the same crash.  
3. Left-turn crashes
   
   • The turning driver must yield to oncoming traffic until the turn can be made with reasonable safety: §21801.  
5. Red-light collisions
   
   • Drivers facing steady red must stop at the limit line/crosswalk and remain stopped until lawfully permitted to go: §21453.  
7. Stop-sign crashes
   
   • You must stop at the limit line/crosswalk: §22450, then yield to vehicles that pose an immediate hazard and proceed only when safe: §21802.
   • (If there’s no control at the intersection, §21800 assigns right-of-way.)  
9. Unsafe lane change / sideswipe
   
   • Don’t move right/left until it’s reasonably safe and you’ve signaled if other traffic may be affected: §22107.
   • Stay entirely within a single lane; only leave it when safe: §21658(a).
   • Signal continuously for the last 100 feet before turning: §22108.  
11. Merging / entering from driveways and lots
    
    • A driver about to enter or cross a highway from public/private property or an alley must yield until it’s safe: §21804.  
13. Speed-related crashes
    
    • CA’s Basic Speed Law: never drive faster than is reasonable or prudent given conditions, and never at a speed that endangers persons/property: §22350.  
15. DUI collisions
    
    • Driving under the influence or ≥0.08 BAC is unlawful: §23152. DUI can support negligence per se arguments in civil cases.  
17. Backing / parking-lot crashes
    
    • Don’t start a parked vehicle or back onto a roadway until it can be done with reasonable safety: §22106.  
19. Pedestrian crosswalk incidents

• Drivers must yield to pedestrians in marked or unmarked crosswalks at intersections: §21950.
• Pedestrians outside crosswalks must yield to vehicles, but drivers still owe due care: §21954.  

Bonus: Bicycle “dooring” is often on the parked driver/passenger—don’t open a door unless it’s safe and doesn’t interfere with traffic: §22517. 

How we actually prove fault (what moves adjusters)

• Video & photos: dashcam, store/traffic cams, intersection approach angles.
• Vehicle data: event data recorders (EDR), airbag modules, speed/brake traces.
• Scene evidence: skid/yaw marks, debris field, point(s) of rest.
• Communications: 911 audio, dispatch CAD, driver admissions, cell-phone use.
• Medical timeline: immediate symptoms, imaging (e.g., MRI for soft tissue), consistent care—gaps get used against you.

Fast FAQs

Is the rear driver always at fault?

Usually, §21703 puts heavy blame on the rear driver—but sudden, un-signaled braking (§22109) can create shared fault. 

Who’s at fault if I turn left and get hit?

Left-turning drivers must yield under §21801—but speeding (§22350) and red-light violations §21453 by the through driver can shift percentages. 

What if there’s no sign or light?

Uncontrolled intersections use §21800 (e.g., driver on the left yields to the driver on the right when they arrive at the same time). 

Ready to get answers for your crash?

We map the facts to the right code sections, send preservation letters, and build the evidence package that moves your claim. Serving Chatsworth, Woodland Hills, Porter Ranch, Simi Valley, and Los Angeles.

Talk to a Chatsworth car-accident lawyer for a fast plan today.