  While it might thus be possible for a researcher to use HESCs without being morally responsible for the destruction of human embryos, that does not end the inquiry into complicity. Some argue that agents can be complicit in wrongful acts for which they are not morally responsible. One such form of complicity arises from an association with wrongdoing that symbolizes acquiescence in the wrongdoing (Burtchaell 1989). The failure to take appropriate measures to distance oneself from moral wrongs may give rise to “metaphysical guilt,” which produces a moral taint and for which shame is the appropriate response (May 1992). The following question thus arises: Assuming it is morally wrongful to destroy human embryos, are HESC researchers who are not morally responsible for the destruction of embryos complicit in the sense of symbolically aligning themselves with a wrongful act?