Well I am sorry to rain on your parade... but Napolitano has established a pattern of backhanded sniping against Trump. It has actually been going on for months. He says negatives things about Hillary also to keep credibility with his audience, but the only time the media really picks it up on his statements is when he says something bad about Trump. So he damages Trump much more than Hillary. And he is smart enough to understand that very well. I thought that he was doing to announce as a “never Trumper” but it would have been bad for his “career”. Here are just a couple of examples, but the supply of negative quotes about Trump from the good judge are voluminous and stretch back quite a ways.
Take Trump Down Is He Right?!?
http://www.thepoliticalinsider.com/judge-napolitano-says-will-finally-take-trump-right/
http://therightscoop.com/judge-napolitano-obliterates-trump-on-his-lack-of-serious-thinking/
Judge Napolitano Blasts Donald Trump On Immigration Plans
http://truthinmedia.com/judge-napolitano-donald-trump-immigration/
He started the primary season supporting Rand Paul
https://alibertarianfuture.com/2016-election/guess-judge-wants-see-elected-president-2016/