In general, yes. There are specific exceptions that apply in certain cases, but cops do not have the right to start blasting away merely because someone's running from them.
Seems the odds are stacked in the criminal's favor if all our BP and police have to tackle every criminal just to apprehend them. There's nothing to stop every one from trying to flee then, either.
I'm about to shock you. Better sit down.
You have exactly as much right--no more, no less--to employ deadly force as a cop on duty does. Being a cop doesn't grant you extraordinary power of life and death merely because they're given a badge. Unless the officer has a specific and reasonable belief that the suspect poses an imminent danger to someone's life and limb, deadly force is not allowed.
The problem here is that (a) these guys got stupid, and (b) they lied about it, and destroyed evidence. The former is not necessarily criminal. The latter is, and demonstrates consciousness of guilt.