The Heller decision takes a stand for originalism:
In interpreting [the Second Amendment], we are guided by the principle that “[t]he Constitution was written to be understood by the voters; its words and phrases were used in their normal and ordinary as distinguished from technical meaning.” United States v. Sprague, 282 U. S. 716, 731 (1931); see also Gibbons v. Ogden, 9 Wheat. 1, 188 (1824). Normal meaning may of course include an idiomatic meaning, but it excludes secret or technical meanings that would not have been known to ordinary citizens in the
founding generation.
This strikes me as important.