Well, you are holding them to higher standards than the average man on the street, aren't you?
I mean, we know nothing about the events prior to, and during this shooting. We have the barest facts; a house was under surveillance, this guy left it in (reportedly) suspicious clothing, the police challenged him, he ran despite repeated warnings, and then he was shot between 2-5 times.
We don't know how the police identified themselves, exactly how or if he was restrained, how he (the victim) was dressed (specifically RE: the eyewitness who said he saw a bomb vest), what the police thought was going on in the house he left, the exact number of rounds (eyewitnesses vary between 2 and 5), how the victim reacted to being challenged and if he acknowledged they were police officers, and soforth.
And it may be that it was a serious, unlawful crime. But I'm not going to hang someone until the facts are known; a (real) suicide bomber is a literal 'kill or be killed' scenario, and I want to know exactly what went on and whether it was sufficient for those police to legitimately believe this was that scenario. That's why we have an independent group with the purpose of investigating exactly this sort of scenario.
As it stands your making the assumption that this police officer is a cold blooded, trigger happy murderer without any actual evidence that would support that; because regardless of policy, it's still the officers choice to pull the trigger.