In some ways, it’s worse to shoot a cop.
Shooting a cop is shooting a representative of all of us. Not the government, but in reality, all of us as people.
Secondly, as citizens, we have the ability to close with or run away from dangerous situations. Cops do not.
Finally, the Black community expects cops to come and save lives when they are being robbed, assaulted, when someone can’t breath, when a senior has a heart attack, when a baby is very sick. They get there before the ambulance, and often it’s the cops who render the immediate action first aid that keeps the victim alive till the EMTs get there.
If it’s OK to kill those people you want come when you need help, why should they come when any call for aid can be a setup for an ambush?
To the extent that most murders happen between people who know one another and the crime is deeply personal in nature, I agree that shooting a public officer is somewhat more heinous, because it is an act of defiance against the entire society's principle of the rule of law.