So, to commit premeditated murder by killing an ordinary citizen is less reprehensible than accidentally and inadvertently killing a policeman in the heat of the moment? How does it feel to be a second class citizen?

In the UK, the police are regarded as public servants. They call me "Sir" not "Buddy" and I call them "Constable" not "Sir".

And if we both faced a lunatic with a gun, he would be expected (morally, only, of course) to take the bullet instead of me.

If it really is because killing a representative of the justice system must be punished more severely, pour encourager les autres, wouldn't it be simpler just to make resisting arrest a capital offence and be done with it?