I have to say that I’ve always thought Potter Stewart is the most underestimated. His knack for phrases that were very memorable and/or perfectly encapsulated a case was incredible - see e.g.
cruel and unusual in the way that being struck by lightning is cruel and unusual (Furman v. Georgia).
one day in prison for the ‘crime’ of having a common cold would be cruel and unusual (Robinson v. California)
swift justness demands more than just swiftness (I forget the case)
Also, his short concurrence in Roe v. Wade seems to do more to explain the basis for the holding more than the majority does.
Other than Stewart, I think highly of Stevens and Souter. Stevens was apparently very impressed by Stewart.
I suppose I have a lot of respect for Scalia even if I very much disagree with him.
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