A brief of the Citizens Committee for the Right to Keep and Bear Arms, and for several scholars, takes an unusual approach. As far as I know, it's the first brief of its kind in a Supreme Court brief (although my knowledge of amicus briefs is far from comprehensive). Written by Washington state lawyer Jeff Teichert, the "Errors Brief" focuses entirely on refuting what it sees as plain errors in the briefs of DC and DC's amici. The 9000 word limit drastically reduced the number of items which could be addressed, and the brief chooses to address some items at relatively great length, rather than greatly shrinking certain discussions so as to address more items briefly.