Source: Richard A. Posner, How Judges Think (2008), p. 351 Bottom.
Furthermore, foreign decisions emerge from a complex social, political, historical, and institutional background of which most of our judges and Justices are ignorant. To know how much weight to give to the decision of the German Constitutional Court in an abortion case, you would want to know how the judges of that court are appointed and how they conceive of their role, and especially how German attitudes toward abortion have been shaped by peculiarities of German history, notably the abortion jurisprudence of the Weimar Republic, thought by some to have set the stage for some of Nazi Germany's legal atrocities, such as involuntary euthanasia. The European rejection of the death penalty, which advocates of abolishing the death penalty in the United States cite as evidence of an emerging international consensus that ought to influence our Supreme Court, is related both to the past overuse of it by European nations (think of the executions for petty larceny in eighteenth-century England, the Reign of Terror in France, and the rampant employment of the death penalty by Nazi Germany and the Soviet Union) and to the less democratic cast of European politics, which makes elite opinion more likely to override public opinion there than in the United States [emboldening mine].
I already know, and ask not about, the Democratic deficit in the European Union. So let's imagine 'Europe' in the emboldened quote to refer to countries in Europe, not the EU. Then how's it true?