With Elena Kagan’s confirmation hearings well underway, her approach to foreign law remains an important concern.

In recent years, Supreme Court justices have increasingly looked to the laws of other nations when interpreting the United States Constitution -- a practice detrimental to the American principle of self-government. Senators should vigorously question Kagan to determine whether she too would sacrifice our sovereignty to the whims of foreign opinion, especially selective foreign opinion.

Kagan’s statements so far are troubling. In a letter written to Senator Arlen Specter before her Solicitor General confirmation, she wrote, “There are some circumstances in which it may be proper for judges to consider foreign law sources in ruling on constitutional questions.” As an example, she discussed the Eighth Amendment “cruel and unusual punishment” line of cases.

But she did not clarify when it might be appropriate to look to foreign law and when it wouldn’t be. In fact, neither has the Supreme Court. The justices who cite it have been curiously selective in their use of it and have never even hinted at a principle behind their cafeteria counter approach.

Yet it’s clear from their jurisprudence that the principle is a political one: some justices look beyond our borders only when doing so would bolster their desired result.

The Court’s habit of looking to world opinion when interpreting the Eighth Amendment’s prohibition on cruel and unusual punishment is a troubling example of things to come. In 2005, the Court used foreign standards as one of three factors leading to its conclusion that executing a 17-year old murderer amounts to cruel and unusual punishment. Foreign laws were considered in the Court’s misguided evaluation of the “evolving standards of decency that mark the progress of a maturing society.” Contemporary foreign laws were apparently more relevant than the Clause’s text or original public meaning in America, to which the Court did not dedicate even a sentence.

The Court looked to foreign law again -- albeit to a lesser degree -- in an Eighth Amendment case this term to determine that juvenile non-homicidal offenders cannot receive life without parole sentences. Before the Supreme Court imbued the Eighth Amendment with foreign law, both of these purely domestic criminal justice issues were decided by the people of the United States through the democratic process.

Deborah O'Malley

Deborah O’Malley is a Research Associate in the Center for Legal and Judicial Studies at The Heritage Foundation. Follow Heritage's continuing coverage of the Elena Kagan nomination.