To rehear a case en banc simply on the basis that it involves an important issue would undermine the three-judge panel system and create an impractical and crushing burden on what otherwise should be, as Rule 35(a) suggests, an exceptional occurrence. See FED. R. APP. P. 35(a) ("An en banc hearing or rehearing is not favored . . . ."). According to statistics kept by the Clerk of the court, in 2002 this court decided 5,190 cases on the merits, more than 98% of which were finally decided by three-judge panels. These decisions are not measures of "rough justice," later to be refined by the en banc court. Unless they decide issues of exceptional importance erroneously, create a direct intra-circuit split, or unless the interests of justice require that the decision be corrected, the opinions of three-judge panels should constitute the final action of this court....

Moreover, Article III judges are by constitutional design insulated from the political pressures governing members of the other two branches of government. We are given life tenure and a secured salary so that, in our unique capacity to "say what the law is," Marbury v. Madison, 5 U.S. (1 Cranch) 137, 177 (1803), we may decide constitutional issues without regard to popular vote, political consequence, or the prospect of future career advancement. Most federal judges do not question the wisdom of this approach. When the federal judiciary is so firmly separated by constitutional structure from the direct influence of politics, we must not undermine that structure by allowing political pressures, polls, or "focus groups" to influence our opinions, even indirectly.

This is not to say that federal judges should be completely sequestered from the attitudes of the nation we serve, even though our service is accomplished not through channeling popular sentiment but through strict adherence to established constitutional principles. The Constitution contemplates occasions when we must be responsive to long-term societal trends — when determining, for example, that which is "cruel and unusual," see Hudson v. McMillian, 503 U.S. 1, 9 (1992), whether in the execution of the mentally retarded, see Atkins v. Virginia, 536 U.S. 304, ___, 122 S. Ct. 2242, 2247 (2002), or the execution of juvenile offenders, see In re Stanford, 123 S.Ct. 472, 474 (2002) (Stevens, J., dissenting from the denial of an application for an original writ of habeas corpus). This broader long-term social conscience, however, is a matter far different from responding to particular immediate political pressures. We may not — we must not — allow public sentiment or outcry to guide our decisions. It is particularly important that we understand the nature of our obligations and the strength of our constitutional principles in times of national crisis; it is then that our freedoms and our liberties are in the greatest peril. Any suggestion, whenever or wherever made, that federal judges should be encouraged by the approval of the majority or deterred by popular disfavor is fundamentally inconsistent with the Constitution and must be firmly rejected.