Supreme court decision that has been handed down?

You are probably referring to the Supreme Court's verdict in the case of Dred Scott, a slave who applied for his freedom on the grounds that he had been employed by his master on free soil.

Unfortunately, he did not make his application until he was back in slave country, and the local courts did not know what to make of the situation. The Supreme Court ruled against Scott, claiming that that the Constitution protected a man's property, and slaves were undoubtedly property. This appeared to mean that slavery could not be banned from any state - a highly incendiary verdict. The Court also declared that a black man had no business suing a white man, which infuriated the Abolitionists, and raised the temperature of the already-overheated slavery debate.