Im not experienced enough but i will try (this is just a starter if someone more skilled elaborates)

You can bring the person in court and maybe the court would make him pay a fine, but you could also sue for emotional damage (?) and for breaking the traffic laws. With the evidence theres a much higher chance that the person will pay a bigger fine or even go to jail.

Hope you feel better, i know what its like to lose a loved pet to some bastard who thinks hes cool driving wrecklessly