## Facts

- Nielsen was a Washington resident and U.S. citizen licensed by Washington to operate a purse net on the Columbia River.
- The Columbia River forms the boundary between Oregon and Washington.
- Congress granted Oregon and Washington concurrent jurisdiction over offenses on the Columbia River where it serves as the common boundary, including in Oregon’s admission act.
- Oregon law made it a misdemeanor to operate a purse net for catching salmon or other specified fish on the Columbia River.
- Washington law expressly permitted purse nets under license, and Nielsen acted under such a license.
- It was stipulated that Nielsen’s fishing occurred within Washington’s territorial limits (on the Washington side of the river).
- Oregon prosecuted Nielsen in Oregon for violating Oregon’s anti–purse-net statute based on this conduct.

## Issues

1. Whether Congress’s grant of concurrent jurisdiction over the Columbia River authorized Oregon to prosecute a person for conduct committed within Washington’s territorial limits that Washington law licensed, even though Oregon law prohibited it.

## Decision

- The U.S. Supreme Court reversed Oregon’s judgment affirming Nielsen’s conviction.
- Oregon could not prosecute Nielsen for using a purse net on the Washington side of the Columbia River when Washington authorized the conduct by license.
- The Court limited its holding to the facts presented and did not decide whether Oregon could prosecute for similar conduct on the Oregon side of the river or whether prosecutions should be brought in the name of both states.

## Legal Principles

- A congressional grant of “concurrent jurisdiction” over boundary waters confers broad adjudicative authority in civil and criminal matters, but it does not eliminate each state’s territorial sovereignty.
- Where concurrent jurisdiction exists, one state may proceed first against conduct criminalized by both states (commonly characterized as *malum in se*), and a resulting judgment bars a later prosecution by the other state.
- That priority-and-finality rule does not apply when the conduct is prohibited only by one state and authorized by the other.
- A state may not use concurrent jurisdiction to enforce its purely regulatory criminal prohibitions (*malum prohibitum*) against acts committed within the other state’s territorial portion of the boundary waters when the other state affirmatively permits the conduct.

## Conclusion

Concurrent jurisdiction over an interstate boundary river is primarily a jurisdictional device to address boundary-line enforcement problems; it does not permit one state to apply its regulatory criminal policy to conduct occurring in the other state’s territory and authorized by that state.


Nielsen v. Oregon, 212 U.S. 315 (1909)