Hmmm, why is the car in front of me braking?

Oncoming car was a Mazda CX-5, whose driver suffered a concussion, broken jaw, broken nose, and fractured leg. Cammer was a Mitsubishi Outlander, and suffered a broken leg. The other vehicle was a Suzuki Grand Vitara. https://www.facebook.com/CaughtOnDashcamsOrCCTV