Reason.com has a piece by Damon Root asking various libertarian and conservative legal experts what they think about the matter. There are a range of answers. Here is my response:
I certainly believe that the future of the Supreme Court is “a reason” to support Trump. There are no assurances, but I do believe it is likely that he will choose someone from the list he issued previously (or someone similar). Is it a strong enough reason to overcome the other reasons not to vote for him?
To me, it depends on one’s perspective. If one is simply voting for the candidate whose views are closest to your own, then most libertarians will vote for Gary Johnson. Trump’s Supreme Court appointments are unlikely to affect that.
But if you are (for some reason) choosing between Trump and Clinton, then Trump’s likely appointments are important. Both Trump and Clinton are so flawed that any significant chance that one of them will do something good is pretty important. So I would say that if one is choosing between Trump and Clinton, then Trump’s likely appointments are a strong reason for preferring him. Of course, that strong reason might be outweighed by other considerations, depending on your views of the two candidates.
Obviously, I am very tentative about the issue. One’s decision here depends on how one views voting; the likelihood that Trump makes a good appointment is uncertain; and much depends on how one evaluates Trump’s other negatives. But the key point is that “both Trump and Clinton are so flawed that any significant chance that one of them will do something good is pretty important.” This is a pretty damning statement, but I am hardly alone in believing this.
The other people who responded are split on these issue. Many believe, like Jonathan Adler, that “Trump is beyond the pale.” Others see the Supreme Court as the main reason to support Trump, viewing the decision as Glenn Reynolds does, as between “certainly awful and possibly awful.” What a political year we are in!
Given how similar the basic political principles are of the experts, it is genuinely interesting that they are so split.