David Ross, plaintiff in error, brought a case against Charles M'Lung, defendant in error. The dispute was over the ownership of certain slaves and their children. Ross claimed that he had purchased them from M'Lung's father-in-law and thus owned them outright. However, M'Lung argued that his father-in-law only held the slaves as security for a debt owed to him by Ross and therefore they were still legally his property. The Supreme Court ultimately sided with Ross on this issue due to lack of evidence presented by M'Lung proving otherwise. This ruling established an important precedent regarding slave ownership rights which would be used in future cases involving similar disputes between parties claiming title to enslaved persons or their offspring.

In the case of David Ross v. Charles M'Lung, the dissenting opinion argued that a contract between two parties should be enforced as written and not interpreted by courts to mean something different than what was agreed upon in writing. The dissent noted that while it is true that contracts can be modified or changed through mutual agreement, this particular contract did not contain any such language indicating an intent to modify its terms. Furthermore, the dissent argued that if one party were allowed to unilaterally alter a contract without consent from both parties then all contracts would become uncertain and unenforceable due to lack of clarity regarding their meaning. As such, the dissent concluded that since there was no evidence of mutual agreement for modification in this case, the court should enforce it according to its original terms as written by both parties at the time they entered into it.