Hancock v. Holbrook & Others was a United States Supreme Court case that dealt with the issue of whether a state court had the authority to issue a writ of mandamus to a county court. The case arose when the plaintiff, Hancock, sought to have the county court issue a writ of mandamus to the defendants, Holbrook and others, to compel them to pay a debt that they had previously agreed to pay. The defendants argued that the state court did not have the authority to issue such a writ. The Supreme Court held that the state court did have the authority to issue a writ of mandamus to the county court. The Court reasoned that the state court had the power to issue such a writ because it was a court of general jurisdiction and the writ was necessary to enforce the rights of the plaintiff. The Court also noted that the writ was necessary to ensure that the defendants complied with their agreement to pay the debt. In conclusion, the Supreme Court held that the state court had the authority to issue a writ of mandamus to the county court in order to compel the defendants to pay the debt that they had previously agreed to pay. The Court reasoned that the writ was necessary to enforce the rights of the plaintiff and to ensure that the defendants complied with their agreement.

Justice Field delivered the dissenting opinion in Hancock v. Holbrook & Others, arguing that the majority had failed to consider certain facts and precedents which should have been taken into account when deciding on a ruling. He argued that there was no evidence of fraud or bad faith by either party in this case, and thus it would be unjust for one side to suffer damages due to an oversight on their part. Furthermore, he noted that both parties were aware of the mistake prior to entering into any agreement; therefore they should not be held liable for any losses incurred as a result of it. Finally, Justice Field stated that if such mistakes are allowed to stand without consequence then similar errors could become commonplace in future contracts between two parties who may not fully understand all aspects of what they are agreeing upon.