In the dred scott case, the supreme court decided a. the missouri compromise was illegal because it freed slaves in the slave states. b. the missouri compromise was illegal because it was illegal for congress to deprive a slave owner of property (slaves) without the due process of law. c. the missouri compromise was illegal because it was illegal for congress to deprive a slave of his or her freedom if they lived in the south. d. the compromise of 1850 was illegal because it was illegal for congress to deprive a slave owner of property (slaves) without the due process of law.