Amicus curiae ("friend of the court") briefs are supposed to allow parties who will be seriously effected by the decision in a live controversy to make their views known to a court, usually an appeals court, to assist the court in reaching the correct legal decision. Supposed to, that is; and they are supposed to be used "only when the court is in danger of making an incorrect decision because a party's position does not adequately represent the vital interests of the amicus." All too often, amicus briefs are tools to either evade the page/volume limits on appellate briefs or mere repetition of the party's arguments.
The most despicable practice, though—one that I have personally seen attempted, and counseled the prospective amicus against signing on to the brief—is filing that amicus brief in coordination with the party, largely (if not entirely) written by the party's counsel. That is not just morally wrong; it is a clear violation of the legal ethics rules. See Rules of Professional Conduct 1.7(b), 1.8(f)–(h). And when this is attempted under a fee-shifting statute—which could, in theory, force the losing side to pay both the winner's own attorney's fees and the attorney's fees run up by the winner's attorneys in representing the amicus—it is even worse. This matters to authors because the Copyright Act includes a fee-shifting provision; it is discretionary, not mandatory like civil rights laws, but nonetheless a substantial possibility. Similarly, the Lanham Act and some state trademark statutes have discretionary fee-shifting provisions, as does the Patent Act. The Eleventh Circuit just noted this problem in Glassroth (the Ten Commandments monument in the Alabama Supreme Court case) and established circuit law that the time an attorney spends on amicus matters may not be shifted to the losing party as part of the basis for attorney's fees.
None of this is to say that there is never a valid purpose for an amicus. For example, there are multiple amici in Ellison, most of whom are proper amici. In my judgment, two of the submissions for the other side were not proper, but they were nonetheless allowed (one by the court, one because we did not consider it worth our while to oppose it). That is not to say that amici and parties can never cooperate; it is only to say that an amicus needs to demonstrate a distinct interest from a party. The courts appear to be slowly moving in this direction, if only to avoid being buried under even more dead trees; four circuits in the past twelve months have specifically questioned wheter certain amicus briefs were merely attempts to evade the page limitation in the Federal Rules of Appellate Procedure. <SARCASM> But there oughta be a law… </SARCASM> or at least a clear rule on the subject, not just rather neglectful judicial discretion as there is now.