Professor Jonathan Adler, in a post on the Volokh Conspiracy, speculates that Justice Souter’s replacement could join a liberal voting block to overturn the Supreme Court’s line of punitive damages cases going back to BMW v. Gore:

Replacing Justice Souter could also have a significant effect is on the Court’s decisions on the due process limitations on punitive damages. Justice Souter joined the five justice majorities in BMW v. Gore and Philip Morris v. Williams limiting the award of punitives on due process grounds, and also wrote the Court’s majority in Exxon Shipping v. Baker, which limited punitive damages under the federal common law of maritime. Again, “liberal” justices are split on this question. Here, however, if Souter’s replacement were to align with Justices Stevens and Ginsburg, it is likely that the Court’s recent punitive damages cases could be overturned.

While it’s certainly possible that Justice Souter’s replacement could shake things up in this area, I’m not sure I agree with Professor Adler. If the new justice aligns with Justice Stevens, the Court would not be likely to overturn BMW v. Gore. It was Justice Stevens, after all, who wrote the majority opinion in BMW v. Gore. Justice Breyer concurred in that opinion, and both justices Stevens and Breyer concurred in the Court’s subsequent opinion in State Farm v. Campbell. That leaves Justice Ginsburg as the only liberal justice opposing the Supreme Court’s application of the Due Process Clause to limit the size of punitive damages awards. It is true that Justice Souter was part of the 5-4 majorities in Williams and Exxon Shipping, so his replacement could potentially lead the Court to overturn those decisions, but the foundations of the Supreme Court’s punitive damages jurisprudence would still be intact so long as the Court does not overturn the BMW and Campbell decisions.