He gives every sign of being a careful constitutionalist--for example, as a believer in federalism and the Lopez line of cases. One signal on this point is his 2003 dissent in Rancho Viejo, in which he questioned a Fish & Wildlife Service order to a developer to move a fence from its own property in order to accommodate an endangered toad.
"The hapless toad," he wrote, "for reasons of its own, lives its entire life in California" and thus could not affect interstate commerce. This implies a less expansive view of the Commerce Clause than the current Supreme Court majority, and suggests he would have joined the four dissenters in Raich, the Supreme Court's recent decision to let the federal government overrule state laws on regulating medical marijuana.
So-called "liberals" should move away from their myopic fixation on abortion, and realize that strict constructionists like Roberts can be great friends of civil liberties supporters. A more reasonable interpretation of the Commerce Clause, which Roberts suggests, is one of the most important possible steps in limiting the reach of an increasingly intrusive federal government.