Missouri v. Holland · US Supreme Court · 1920

Does the treaty let Congress regulate?

Short answer: Yes: treaties can give that power.

The facts. Congress's first law protecting migrating birds was struck down by lower courts. So the US signed a treaty with Britain on behalf of Canada, then passed a new law. Missouri sued a federal game warden to keep its hunting rights.

The ruling. Missouri v. Holland (1920): Justice Holmes held that a valid treaty supports a law Congress couldn't otherwise pass, adding that birds know no state lines.

Holmes wrote that the Constitution must be read as a living organism. The ruling on treaty power remains controversial a century later.

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For fun, not legal advice.