Packet Company v. Keokuk was a United States Supreme Court case that dealt with the issue of whether a city could be held liable for damages caused by a bridge it had built. The case arose when the Packet Company, a steamboat company, sued the City of Keokuk, Iowa, for damages caused by a bridge the city had built across the Mississippi River. The bridge was built without the permission of the United States Congress, and the Packet Company argued that the bridge was an obstruction to navigation and caused them damages. The Supreme Court held that the City of Keokuk was liable for the damages caused by the bridge. The Court reasoned that the city had acted negligently in building the bridge without the permission of Congress, and that the bridge was an obstruction to navigation. The Court also held that the city was liable for the damages caused by the bridge, even though the bridge was built for a public purpose. The Court reasoned that the city had a duty to ensure that the bridge did not interfere with navigation, and that it had failed to do so. The Court's decision in Packet Company v. Keokuk established that cities can be held liable for damages caused by bridges they build, even if the bridges are built for a public purpose. The decision also established that cities have a duty to ensure that their bridges do not interfere with navigation.

In Packet Company v. Keokuk, the Supreme Court was asked to determine whether a city could be held liable for damages caused by its negligence in failing to maintain a bridge over the Mississippi River. The majority opinion found that the city of Keokuk had no legal obligation to keep up and repair the bridge, as it was not part of any public highway or navigable river. However, Justice Field dissented from this ruling on two grounds: firstly, he argued that under common law principles of liability cities should be responsible for maintaining bridges which are used by citizens; secondly, he noted that Congress had passed legislation granting authority to states and municipalities “to construct works across rivers” – thus implying an obligation on their part to ensure such structures were safe and usable. In conclusion then, Justice Field believed there was sufficient evidence for holding Keokuk accountable for damages resulting from its failure in keeping up with repairs on the bridge in question.