"There have been suggestions to impeach federal judges who issue decisions regarded by some as out of the mainstream." ...
Chief Justice Rehnquist said ... that it had been clear since early in the country's history that "a judge's judicial acts may not serve as a basis for impeachment."
"Any other rule," he added, "would destroy judicial independence," since "judges would be concerned about inflaming any group that might be able to muster the votes in Congress to impeach and convict them."
What "suggestions" is he referring to? Greenhouse cites the House Reaffirmation of American Independence Resolution, which states that "inappropriate judicial reliance on foreign judgments, laws or pronouncements threatens the sovereignty of the United States, the separation of powers and the president's and the Senate's treaty-making authority." One of the resolution's sponsors alluded to impeachment as a remedy. It's hard to imagine that any judge feels any kind of threat of impeachment merely for citing foreign law. The resolution refers to "inappropriate ... reliance" on foreign law. Presumably, at some point, the use of foreign law really would damage United States sovereignty to the point where a judge ought to be removed.
I don't agree with the bright line rule Rehnquist seems to proclaim: a judge ought never to be removed for anything he does as a judge. (I'm not looking at the full text of the report as I write that.) And I don't see why judicial independence is "destroy[ed]" simply because a judge would be "concerned" about motivating people to call for his impeachment. Federal judges have extremely secure positions, founded on the Constitution's provision for lifetime appointments. But the Constitution also provides for impeachment, and some pushback against judicial power is a good thing. The demand for an absolute rule against impeachment for "judicial acts," lest the judge feel any pressure from the political sphere, is actually quite extreme.
Anyway, this issue of using foreign law is a lively current issue, and I note that Justices Scalia and Breyer are going to have a big debate on the subject at American University in Washington, D.C. on January 13th. My old conlawprof, Norman Dorsen, is going to moderate. Too bad I can't attend. I'm mean, too bad I'm not going to travel to Washington just to attend. But I see they are going to livestream, and I'm planning to simulblog.