Now that the votes in Dobbs are finalized, we can look back at the case with the benefit of hindsight. At conference, it now seems clear that Justice Alito's position had five solid votes. Chief Justice Roberts was intent to write a concurrence in judgment based on "reasonable notice." He signaled this position during oral argument. (I will write about that concurrence in another post). I think it reasonable to infer that Justice Thomas assigned the majority opinion to Justice Alito. I suppose it is possible that the Chief Justice was cagey, and assigned the opinion to Alito, knowing that he could break away later. But I think it would be tougher for Roberts to commit to agreeing with Alito, at least in principle, only to later change his mind. NFIB already played that script.
Another related factor: the S.B. 8 case. Whole Woman's Health v. Jackson was argued on November 1, 2021. Dobbs was argued one month later on December 1, 2021. And Jackson was decided on December 10, 2021. By the time Jackson was decided, the majority to overrule Roe was established. I think that outcome may have made it easier for the Court to allow the enforcement of the fetal heartbeat law. Texas cannot "nullify" a constitutional right that the Supreme Court was prepared to overrule. Indeed, the joint dissent in Dobbs referenced the relationship between S.B. 8 and the Mississippi case:
Earlier this Term, this Court signaled that Mississippi's stratagem would succeed. Texas was one of the fistful of States to have recently banned abortions after six weeks of pregnancy. It added to that "flagrantly unconstitutional" restriction an unprecedented scheme to "evade judicial scrutiny." Whole Woman's Health v. Jackson (2021) (Sotomayor, J., dissenting). And five Justices acceded to that cynical maneuver. They let Texas defy this Court's constitutional rulings, nullifying Roe and Casey ahead of schedule in the Nation's second largest State.