1) Accidentally or not, attacking another player will make you a most wanted criminal (6 star wanted level). In your case, you rammed the cop with your car.
2) Cops are allowed to kill most wanted players on sight so [RA]Stormi and z0Re67 did not break any rule by killing you.
3) Use /actions to see details of who shot / killed you (many other details can be seen).
Invalid report.