I would assume everyone is on official duty. Remember: The UN GA is in town and there are extra deployments to midtown and the East Side. I'm not justifying their use of a "No Standing" zone but I am offering a reasonable explanation for their actions

No you're not. Personal vehicles are not used by law enforcement for official use and blocking an emergency vehicle in transit to or from an emergency with ANY type of vehicle is illegal if you are Bloomberg from on high hisself.

Actually Saint, you CAN use personal vehicles for official use -- that's why there are placards. It's just that much of their use is actually abuse.

How is he blocking an emergency vehicle? His car is parked. If it wasn't him it would be a livery cab Town Car standing in the zone waiting for a passenger or a truck parked there because all the commercial spots are taken.

There are placards for official vehicles to park on business, and there are placards for personal vehicles to sit in very specific areas whilst the owner is using said official vehicle. If anything else is the case, it is likely not nearly on the scale as this and would therefore be a minor consideration. As for blocking "The two cars in the foreground of this photo have police parking permits, in a No Standing turn lane" If people get jammed up behind people trying to turn because someone blocks the turn lane, whaddya know! Traffic jam!
And will, all the other situations you iterated would be almost as bad, and just as illegal. I say almost as bad because breaking the law is even more tasteless when you're supposed to be an upstanding example of lawfulness as an enforcer of it.

Saint, you say "Personal vehicles are not used by law enforcement for official use". That is incorrect. Many cops are forced to use their own cars for transportation to many events all over the city, they should have to do this, but they have little other opption sometimes.

Then you go on to say "blocking an emergency vehicle in transit to or from an emergency with ANY type of vehicle is illegal". To bad these guys arn't doing that. These cars are parked along the curb, out of the lane of travel. If they were parked across the street blocking the entire street, then they would be more wrong, but even then they could not be charged with "blocking an emergency vehicle" because that requires intent, not just the "luck" of an ambulance coming down that block.

Correction:

I ment to say: "they SHOULDN'T have to do this, but they have little other option sometimes."