From NYT Sunday Book Review:

Of course, such a pragmatic approach can engender controversy, as one line of this book has already done. Posner writes, “I plead guilty to having written the majority opinion (affirmed by the Supreme Court) upholding Indiana’s requirement that prospective voters prove their identity with a photo ID — a type of law now widely regarded as a means of voter suppression rather than of fraud prevention.” This line has been interpreted as a recantation, yet it’s less an admission of error than an admission of uncertainty. This is consistent with his general approach: to acknowledge complexity, vacuum up as many facts as possible and then do his best.