That’s the problem...they WERE doing their job, as defined by those elected by the people of Denver to determine what the job of the police is and how it should be done. They give the orders and those orders are “legal”. The real problem is who has been put in power over the police and their philosophy...the people of most American cities have elected veritable communists into power...so you will get communist (political) policing in those jurisdictions.
If that is the extent of your argument, and history aside blindly following "orders" usually ends up with a injured party, and to say that I was just following orders ignoring the civilians being assaulted is in contravention to the law.
To stand down while someone gets assaulted proves that your there for a paycheck and not protecting those under your purview. Which falls under seditious conspiracy, misprision of felony.
And make the offender who did nothing a worthless POS.
And to say "just following orders" is what the Nazi's used in their defense at Nuremberg.