St. Louis Street Foundry v. United States was a Supreme Court case that addressed the issue of whether the United States government was liable for damages caused by the construction of a public work. The case arose when the United States government constructed a levee along the Mississippi River in St. Louis, Missouri. The construction of the levee caused the St. Louis Street Foundry to suffer damages due to flooding. The Foundry sued the United States government for damages, arguing that the government was liable for the damages caused by the construction of the levee. The Supreme Court held that the United States government was liable for the damages caused by the construction of the levee. The Court reasoned that the government had a duty to exercise reasonable care in the construction of the levee, and that the government had failed to do so. The Court also held that the government was liable for the damages caused by the construction of the levee, even though the government had not intended to cause the damages. The Court reasoned that the government had a duty to exercise reasonable care in the construction of the levee, and that the government had failed to do so. The Court's decision in St. Louis Street Foundry v. United States established the principle that the United States government is liable for damages caused by the construction of public works, even if the government did not intend to cause the damages. This principle has been applied in numerous cases since the decision in St. Louis Street Foundry v. United States, and has become an important part of the law governing the liability of the United States government.

In St. Louis Street Foundry v. United States, the Supreme Court was tasked with determining whether a contract between the two parties had been breached by the government when it failed to pay for goods and services provided by the foundry. The majority opinion held that since there was no written agreement between them, there could be no breach of contract as defined under federal law at that time. However, in his dissenting opinion Justice Field argued that even though there may not have been a formal written agreement, an implied contract existed based on their dealings and past practices which should be recognized as legally binding under federal law. He further argued that if this were not accepted then any party who did business without a formal written agreement would find themselves unprotected from potential breaches of trust or other wrongs committed against them by another party - something he felt would lead to injustice and unfairness in many cases such as this one where goods or services had already been provided but payment refused due to lack of a legal document outlining terms of service beforehand.