They did get involved when they started assaulting people though.
It's an odd article, particularly this very contradictory paragraph:
The group of more than 100 hooded protesters, with shields emblazoned with the words "no hate" and waving a flag identifying themselves as anarchists, busted through police lines, avoiding security checks by officers to take away possible weapons. Then the anarchists blended with a crowd of 2,000 largely peaceful protesters who turned up to demonstrate in a "Rally Against Hate" opposed to a much smaller gathering of right-wing protesters
How can you be quite obvious, what with the black clothing and the hoods and flags and shields, but still be able to blend into the crowd?
Well obviously they let them through, how else are they going to beat up those ebil racist misogynist xenophobic homophobic bigot nazis for supporting the current sitting president? They are an inclusive community after all.
Police supporting the anarchists against the right wingers... something of a new one there. Isn't it usually the other way round?
Maligned by the left for their failures in Charlottesville, maligned by the right for Berkeley. The cops just can't win, can they?