It seems that one's right to freedom of expression stops short of endangering the lives of others by driving like a maniac to encourage others to read one's political statement.  The content of the  political statement appears to have been incidental to the conviction.

Zabel's conduct was neither as reckless, nor as partisan.  The hat's message, while imprudent for a judge to display in court, was tangential to the politics of the jurisdiction in which he serves.  

Anyone who correctly predicted that election outcome should be forgiven for having overplayed their hand slightly when proven correct.  Being correct says very little about one's politics; rather it speaks to the sagacity of one's judgement.