Your claims that the DC police are unconstitutional is, at best, a legal sidestep on the topic. It does not really matter. There has to be some sort of local law enforcement for DC. Whomever it would be would have patrols out and would have discovered the same thing.
The story didn't involve the DC police according to the OP. The capitol police are a different agency.
Once again, show me in the Constitution where congress has the power to operate a police force that doesn't answer to the executive branch.Two Capitol Police officers were sweeping the area with police canines
.