 He attacked much of the Supreme Court's decision as "obiter dicta" that was not legally authoritative on the ground that once the court determined that it did not have jurisdiction to hear Scott's case, it should have simply dismissed the action, rather than passing judgment on the merits of the claims.The dissenting opinions by Curtis and McLean also attacked the Court's overturning of the Missouri Compromise on its merits.They noted that it was not necessary to decide the question and that none of the authors of the Constitution had ever objected on constitutional grounds to the Congress's adoption of the antislavery provisions of the Northwest Ordinance passed by the Continental Congress or the subsequent acts that barred slavery north of 36°30' N.

Chief Justice Taney's majority opinion in "Dred Scott" was "greeted with unmitigated wrath from every segment of the United States except the slave holding states."