Step 1: Don't move yet — assess for injuries first. Rear-end whiplash injuries are notorious for delayed onset. Adrenaline at the scene masks neck, upper back, and shoulder symptoms that show up 24-72 hours later. Sit still for 30 seconds. Move your head slowly side to side, then up and down. Note any pain, dizziness, or tingling in your arms. If anything feels off, call 911 — paramedics document at-scene symptoms in a way that matters for medical claims later. Even if you feel fine, see a doctor within 72 hours; many AZ injury attorneys won't take cases where the first medical visit is more than a week post-accident.
Step 2: Get the vehicles out of traffic if drivable. Arizona's "quick clearance" law (ARS §28-674) explicitly protects you from being held at fault solely for moving a drivable vehicle off the main roadway before police arrive. Hazards on. If anyone is hurt or vehicles aren't drivable, leave them and get yourself to the shoulder. Phoenix-area freeway secondary collisions kill more people than primary rear-ends — don't stand between vehicles, don't try to push a car off the road by hand.
Step 3: Document like the case depends on it (it might). Photograph: damage to both vehicles from front, rear, and both sides; the position of cars before they're moved (if you have time); license plates, insurance cards, driver's licenses; the driver's face if they're cooperative; any skid marks, debris, or fluid trails; the road conditions and traffic signals; nearby landmarks for location reference. 30+ photos minimum. Take a short video panning the scene. AZ rear-end fault under ARS §28-730 can still be contested — the rear driver may claim you brake-checked them, were stopped in traffic illegally, had non-functioning brake lights, or stopped suddenly without cause. Your photos defeat those claims.
Step 4: Exchange information and get witness contact. Get the other driver's full name, phone, address, insurance carrier, policy number, vehicle plate and VIN, and driver's license number. Photograph their insurance card and license. Witnesses are gold in disputed-fault rear-ends — get phone numbers from any bystander who saw what happened. Arizona requires drivers to file accident reports involving injury or death under ARS §28-667; for damage-only minor accidents, Phoenix-area department response policies vary, though officers will typically document the scene if asked. For anything involving injuries, always call 911 — the police record becomes primary evidence.
Step 5: File the claim with the right carrier. The at-fault driver's liability owes you full repair, rental at no cost, medical bills, lost wages, and pain-and-suffering. File a third-party claim with their carrier first if they're insured and accept fault. If fault is disputed or they're uninsured, file with your own collision (your deductible applies, then your insurer subrogates). Most AZ insurers issue a claim number within 10 minutes by phone or app. Bring the claim number to a body shop the same day if possible.
Step 6: Watch for hidden vehicle and body damage. Vehicle: rear-end collisions hide damage in the trunk floor, rear frame rails, fuel tank straps, exhaust, and rear suspension. Most shops find $1,500-$4,000 in hidden damage on what looks like a $1,200 bumper job. Don't accept a quick parking-lot estimate — insist on teardown. Body: cervical strain, mid-back muscle tears, TMJ from headrest impact, and concussion symptoms (headache, brain fog, sleep disruption) commonly emerge 1-3 days post-accident. See a doctor anyway, document everything in writing, and keep every receipt for medical co-pays, prescriptions, mileage to appointments, and lost work hours.