Jacob P. Wilson brought a case against Daniel Barnum in the United States Supreme Court, claiming that he had been wrongfully deprived of his freedom by being held as a slave. He argued that he was born free and should not have been enslaved. The court found that although there were some discrepancies between the facts presented by both parties, it could not be determined whether or not Jacob was actually born free or if he had ever been legally emancipated from slavery. As such, they ruled in favor of Barnum and denied Wilson's claim for relief on the grounds that no evidence existed to prove his status as a freeman at birth or emancipation thereafter. This ruling set an important precedent regarding how courts must approach cases involving individuals who claim to have been unlawfully enslaved without sufficient proof of their legal status prior to enslavement

In the case of Jacob P. Wilson v. Daniel Barnum, Justice McLean delivered a dissenting opinion in which he argued that the complainant had not established sufficient grounds to support his claim for damages against Barnum. He noted that while it was true that Barnum had made false representations about certain property, there was no evidence presented to show any actual damage suffered by Wilson as a result of these misrepresentations. Furthermore, even if such damages could be proven, they would have been too remote and speculative to justify an award of compensation from Barnum under existing law at the time. Therefore, Justice McLean concluded that Wilson's complaint should be dismissed without prejudice and with costs assessed against him rather than against Barnum as requested by Wilson in his original petition before the court.