The ACLU has long opposed government limits to how much a donor can give to a political campaign or spend airing advertisements on an issue during an election. On this point, the ACLU has been in agreement with conservative organizations that believe money contributions are a form of political speech and deserving of First Amendment protection. It has been at odds with many liberal organizations, which have argued money in politics must be strictly limited so that rich organizations and individuals don't wield outsize influence.

But Thursday's Supreme Court decision in Citizens United v Federal Election Commission, which would enable corporations to spend freely on political causes, is forcing the ACLU to address what one internal memo describes as a "Skokie moment," a reference to the controversy in which the organization defended the right of American Nazis to march in the Chicago suburb of Skokie. The moment is often seen as one of the acid tests of the ACLU's willingness to stick to its First Amendment principles.