An amicus curiae literally, "friend of the court", is an independent party that submits a brief to a court to alert it to issues not fully addressed by the plaintiffs or defendants, or to support one side of the case.
Each federal Circuit, and the U.S. Supreme Court, has its own rules and customs concerning amicus briefs. For example, the First Circuit does not consider an argument raised by an amicus brief which had not been raised or properly preserved by a party:
|“||This argument was not raised below, and we repeatedly have held that '[w]hile amicus briefs are helpful in assessing litigants' positions, an amicus cannot introduce a new argument into a case.' United States v. Sturm, Ruger & Co., 84 F.3d 1, 6 (1st Cir. 1996); accord Lane v. First Nat'l Bank of Boston, 871 F.2d 166, 175 (1st Cir. 1989).||”|
Gonzalez-Droz v. Gonzalez-Colon, 660 F.3d 1, 12 (1st Cir. 2011).
- Tech Law Journal http://www.techlawjournal.com/glossary/legal/amicus.htm Amicus Curiae