Kind of addressed your as of yet unspoken ETA, but I'm unclear as to whether you're okay with that. I'm not.I agree.
I would say small difference.
Individual police officers don't decide policy, yet we are societally comfortable with people protesting their actions WHILE they are doing them.
ETA
Forgot to address the "off duty" portion. I know of anecdotes where individual officers, while off duty, were confronted about actions that occurred while on duty. Didn't make the news, but that doesn't mean it didn't happen.