The Blackwall was a case heard by the United States Supreme Court in 1869. The case involved a dispute between the owners of the Blackwall, a British-registered vessel, and the owners of the cargo it was carrying. The cargo owners had sued the vessel owners for damages, claiming that the vessel had been negligently operated and that the cargo had been damaged as a result. The Supreme Court held that the vessel owners were liable for the damages, as they had failed to exercise due care in the operation of the vessel. The Court noted that the vessel had been operated in a manner that was not in accordance with the accepted standards of the day, and that the vessel owners had failed to take reasonable steps to ensure the safety of the cargo. The Court also held that the vessel owners were liable for the damages even though the vessel was registered in a foreign country, as the vessel was operating in American waters at the time of the incident. The Court's decision in The Blackwall established the principle that vessel owners are liable for damages caused by their negligence, regardless of the vessel's country of registration. This decision has been cited in numerous subsequent cases involving maritime law, and has been used to establish the principle that vessel owners must exercise due care in the operation of their vessels.

In The Blackwall, the Supreme Court was asked to decide whether a shipowner could be held liable for injuries sustained by an employee while working on board. Justice Field delivered the dissenting opinion, arguing that the owner of a vessel should not be held responsible for accidents occurring on board unless it can be shown that they were caused by his negligence or want of skill in managing her. He argued that Congress had never intended to impose such liability and noted that there was no precedent in English law which would support this position. Furthermore, he argued that if owners were made liable for all accidents occurring aboard their vessels then insurance rates would skyrocket and shipping costs would become prohibitively expensive. As such, he concluded that imposing liability upon shipowners without proof of negligence or lack of skill was unjustified and contrary to established principles of maritime law.