How did the University violate Prince Purple's rights?

San Fransisco University v Prince Purple

The review board of the University System for the State of California is investigating a ruling by the San Francisco State University regarding a student's social media activity.

You are on the review board for the University System. Prince Purple has been cited for violating the Respectful Campus Policy and Social Media Policy.

Facts

• Prince Purple was a 22-year-old law school student at the University Hard Knocks School of Law.
• After President Nelson's reelection, he posted a Facebook status expressing frustration with Democrats "celebrating" abortion.
• He wrote: All right, I've had it. To all of you who support the Democratic candidates:

The Republican Party sucks. But guess what. Your party and your candidates parade their depraved belief in legal child murder around with pride. Disgusting, immoral, and horrific. Don't celebrate Nelson's victory tonight, you sick, disgusting people. You're abhorrent.

Shame on you for supporting the genocide against the unborn. If you think gay marriage or the economy or taxes or whatever else is more important than this, you're f---ing ridiculous.

You're WORSE than the Germans during WW2. Many of them acted from honest patriotism. Many of them turned a blind eye to the genocide against the Jews. But you'recelebrating it. Supporting it. Proudly proclaiming it. You are a disgrace to the name of human.

So, sincerely, f--- you, Moloch worshiping a--holes.

• Several students and a faculty member reported the post to the Dean of Students, who had Prince appear before the Committee on Student Performance and Enhancement (CSPE). The essence of the complaints was that Prince had violated the school's focus on professionalism and civility. Before the hearing, he was discouraged from arguing "free speech" before the panel.
• After his hearing, the panel found his Facebook post was "unprofessional" and violated the University's Respectful Campus Policy and the Law School's Social Media Policy.
• CSPE required Prince to write two reflective papers on professionalism, to write an apology letter, to re-write the Facebook post to express the same views in a professional manner, and to meet with a professionalism advisor monthly for a year.
• CSPE also placed a "notation of professionalism violation" on Prince's record, which would be sent with all law school transcripts/references.