Nicoulin v. O'Brien

Background

A person was convicted under a Kentucky law for using a seine to catch fish in the Ohio River south of the low‑water mark on the Indiana side. The state’s courts upheld the conviction and the case reached the Court to decide whether Kentucky lacked power to regulate fishing there. The defendant argued that a provision of an old Virginia Compact made river use free and required that Kentucky could not regulate the river without Indiana’s concurrence. The opinion notes that Kentucky’s territorial limits extend to the low‑water mark on the northerly shore.

Reasoning

The central question was whether the compact’s clause creating concurrent jurisdiction stripped Kentucky of authority to pass conservation rules inside its boundaries. The Court said it did not. The memorandum explained that establishing concurrent jurisdiction does not prevent a state from protecting fish within its own territory by proper legislation. The opinion relied on earlier decisions for that principle and concluded that Kentucky law could reach the seining conduct at that location, so the conviction should stand.

Real world impact

The decision confirms that a state can enforce its fishing and conservation laws up to its river boundary at the low‑water mark even when older agreements create shared rights along the river. Fishermen and businesses working on the water must obey the law of the state that controls the riverbed to that mark. The judgment simply affirms the lower court’s criminal conviction and leaves questions about interstate coordination over navigation and other shared uses to be addressed separately.