When he refused to show his ID, he was then asked (probably very politely) to leave the premises by the Campus Security officer (the person charged with enforcing school safety and security rules).
When he refused to leave the premises after being asked to leave by the Campus Security officer, he then became a trespasser. His willful refusal to leave was a misdemeanor under Penal Code section 602.1(b).
I'm with you up to here, my FRiend, but this is where we part company on the issue. When the police arrived on the scene, did they intend to arrest him for misdemeanor trespassing (doubtful), or did they intend to simply remove him from the building (more likely)? If their intent was to arrest, then they botched it. If their intent was to remove him from the building, he was already doing it for them.
Sun Tzu said the best way to win a battle is to win before the battle starts. The police officers had that option, but they chose poorly.
So they get fired? Their careers are ruined because of this punk? The taxpayers pay out millions?
Sorry, but they may not have acted perfectly, but they acted legally. He was combative. Now maybe the cops contributed to it by giving hthe jerk an opportunity to turn this little incident into a federal case, but the blame is with him and not with the officers. Unlike you and me, they were not given the opportunity to look at this situation in hindsight. They had to make decisions in real time.
There are mistakes made in every situation. When you become perfect, then you earn the right to second guess others. I suspect there are times in your LEO career where you made a mistake or two, but there weren't 50 people around with video phones and anti-cop attitudes to ensure that you lost your career over it.
You are assuming the version in the student paper that the man was on his way out is true. What if he was not leaving and in fact went limp as the officers attempted to escort him out as the officers claim?