I recently ran across an article containing this:
The [Capitol Police] officer even described coming face to face with police officers from across the country in the mob. He said some of them flashed their badges, telling him to let them through, and trying to explain that this was all part of a movement that was supposed to help.
Now this is interesting. You see, there was some truly shocking behavior on display at the Capitol on Wednesday. We saw Capitol Police officers opening barricades to let rioters in. We saw officers stand aside and let rioters pass. We saw officers retreat without making the slightest effort to engage the mob and thwart its progress. We saw officers helping rioters up and down the Capitol steps. We saw officers posing for selfies with rioters.
At first glance, this points to fifth columnists amongst the Capitol Police. But wait, that puzzle piece really does not fit very well. Why didn’t the plot leak out (conspiracies are hard to keep secret)? Why did some officers still attempt to defend the Capitol and the officials therein?
The claim in the quote above fits far better.
Cops are known to lean right. Many of them are big fans of Trump. One of the reasons people become a cop is that they are authoritarians who get their jollies pushing other people around (what better job than one that allows you to do so legally). Trump is an appealing figure to this sort of person.
Cops give other cops special treatment. It even goes so far as many of them giving their friends and family special “get out of jail free” cards.
There is no special conspiracy at play in the following scenario: just the normal, well-known, institutional rot in policing. Off-duty cops from other departments showed up in the mob, migrated to the front of it, flashed their badges, and got special treatment. Once the barricades had been opened, the rest of the mob streamed through. By the time the violent and destructive intent of the mob was clear, it was too late: the Capitol had already fallen.
The whole problem was then made worse by the fascist element within the Capitol Police who sympathized with the rioting. This could have also affected the lack of preparation on the part of the Capitol Police: they sympathized with the coming mob, so they were not interested in doing a good job of preparing to protect the Capitol.
But there was no conspiracy. It was, to reiterate, simply normal and well-known systematic rot at play.