Laws are worth zero if the law enforcers ignore them with impunity - a lesson familiar from Caribbean and African banana republics.
I think it's a lesson America is currently learning...
Basically it sounds like her understanding is that they are only required to present ID when they take a police action? But I don't understand why blocking a street would not be a police action.
DC Metro attempting to arrest Bureau of Prisons employees when they fail to identify sounds like a complete mess.
It might not be the justice people want, but taking away people's money is the most effective means of instituting change in the USA. It's entirely the reason that company's try to eliminate our right to sue them.