Gelpcke et al. v. The City of Dubuque was a case heard by the United States Supreme Court in 1863 that dealt with taxation and municipal bonds. At issue was whether or not the city of Dubuque had the right to tax certain bonds issued by it for public improvements, which were held by Gelpcke and other citizens of Iowa who had purchased them from their original holders. The court ruled in favor of Gelpcke et al., holding that when a municipality issues its own bonds, those bonds are exempt from taxation unless there is an express provision authorizing such taxes written into the bond itself or some other statute providing for such taxes. This ruling established important precedent regarding municipal debt obligations and how they can be taxed going forward.

In Gelpcke et al. v. The City of Dubuque, the Supreme Court was asked to decide whether a municipal corporation had the authority to issue bonds and levy taxes for the purpose of funding internal improvements such as roads and bridges. Chief Justice Taney delivered a dissenting opinion in which he argued that while states have broad powers under their police power, municipalities do not possess any inherent right or power to tax citizens or borrow money from them without explicit authorization from state legislatures. He further stated that if Congress were allowed to grant this type of authority then it would be an unconstitutional delegation of legislative power since only states can pass laws concerning taxation and borrowing money within their borders. Finally, he concluded by stating that allowing cities like Dubuque to exercise these types of powers could lead other cities down a slippery slope where they are able to enact whatever laws they deem necessary without proper oversight from state governments.