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New Hampshire v. Maine

Supreme Court of the United States · 2001 · Civil Procedure

Civil ProcedureJudicial EstoppelPreclusionjudicial estoppelinconsistent positionsequitable doctrineintegrity of judicial processconsent judgment

Facts

A 1740 decree fixed the boundary between the States at the "Middle of the River." In 1976-1977 litigation over the lateral marine boundary, New Hampshire and Maine agreed in a proposed consent decree that "Middle of the River" meant the middle of the Piscataqua River's main channel of navigation, and this Court accepted that interpretation in entering the consent judgment. In this later original action, New Hampshire asserted that the inland river boundary instead runs along the low-water mark on the Maine shore, which would give New Hampshire sovereignty over the entire river, all of Portsmouth Harbor, and the Portsmouth Naval Shipyard area. Maine argued that New Hampshire could not now adopt a position inconsistent with the one it successfully advanced in the earlier litigation.

Issue

Whether New Hampshire is judicially estopped from asserting in this action that the Piscataqua River boundary runs along the Maine shore after it previously agreed, and the Court accepted, that "Middle of the River" meant the middle of the river's main channel of navigation. More broadly, the question is when judicial estoppel bars a party from taking a position inconsistent with one successfully maintained in prior litigation.

Rule

Judicial estoppel is an equitable doctrine invoked at a court's discretion to protect the integrity of the judicial process by preventing a party from deliberately changing positions according to the exigencies of the moment. Factors that typically inform its application are: (1) the later position is clearly inconsistent with the earlier position; (2) the party succeeded in persuading a court to accept the earlier position, creating a risk that either the first or second court was misled if the later inconsistent position is accepted; and (3) the party would derive an unfair advantage or impose an unfair detriment on the opposing party if not estopped. These factors are not inflexible prerequisites or an exhaustive formula.

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One of 10 multiple-choice questions for this case. Pick an answer to see why.

In a water-rights dispute in Colorado, Pine Valley Water District and Red Mesa Irrigation District jointly asked a state court to enter a consent judgment defining a 1912 easement's phrase "center line" as the midpoint of the canal's maintained flow channel. The court entered judgment on that basis. Fifteen years later, Pine Valley sued over an upstream segment of the same easement and argued that "center line" actually means the outer edge of Red Mesa's bank, which would give Pine Valley control of the entire canal bed there.

Which is the strongest argument for barring Pine Valley's new position under judicial estoppel?

Explanation. Judicial estoppel is an equitable doctrine used to protect the integrity of the judicial process. A principal factor is whether the later position is clearly inconsistent with the earlier one. Here, Pine Valley first urged a mid-channel reading and now urges a bank-edge reading for the same phrase along the same line. The majority opinion emphasized that such a sharp shift strongly supports estoppel, especially when the earlier position was accepted by a court.