Does a constitutional error in a federal criminal case require a reversal of a conviction?

Since the landmark decision in Chapman v. California (1967) 386 U.S. 18, 87 S.Ct. 824, 17 L.Ed.2d 705 (Chapman ), it has been well established that a constitutional error does not automatically require a reversal of a conviction. In Chapman , the court stated "there may be some constitutional errors which in the setting of a particular case are so unimportant and insignificant that they may, consistent with the Federal Constitution, be deemed harmless, not requiring the automatic reversal of the conviction." (Id . at p. 22, 87 S.Ct. 824.)