Sic may show that an uncommon or archaic expression is reported faithfully,[12] such as when quoting the U.S. Constitution: "The House of Representatives shall chuse [sic] their Speaker ..." However, several writing guidebooks discourage its use with regard to dialect, such as in cases of American and British English spelling differences.
And now I'm imagining some spiteful asshole editor putting a [sic] after every -our or -isation that he sees.