K.A. Appiah, in his "Experiments in Ethics" (2008), gives a rather drastic picture of the attack virtue ethics finds itself under by moral psychology.
In a nutshell, (a vast amount of) experiments arguably not only show that people are biased in their ethical decisions by normatively the most irrelevant negligibilities (-> weak character). They act so systematically inconsistent when taking moral action in general that the concept of character traits, the concept of stable dispositions, shaping these actions is no longer tenable (-> no character).
The concept of virtuous character runs the risk of being part of a fictuous story philosophers tell when discussing what should shape our decisions and acts (justification) and what does shape our decisions and acts (explanation). Character building, a traditionally important brick of virtue ethics, becomes part of this story.
Psychology goes on to offer its own explanations of what triggers moral action. Jesse Graham et al. (2013) argue for up to six moral modules which may fire and trigger rapid and affective judgements when an ethically critical situation occurs.
Now, according to Hursthouse/Pettigrove (2018, p. 28), these arguments have "[...] left traditional virtue ethicits unmoved [...]", although "[...] it has generated a healthy engagement with psychological literature."
This seems to me a mildly underwhelming reaction. Is virtue ethics in denial? Is it keeping up pure conceptual analysis with no serious cooperation with moral psychology? Against the background of the empirical results and from the point of philosophy of science, are pure analytical investigations into virtues still justifiable?
References:
Appiah, K.A: Experiments in Ethics. HUP, 2008.
Graham, J., Haidt, J., Koleva, S., Motyl, M., Iyer, R., Wojcik, S. P., & Ditto, P. H. (2013). Moral foundations theory: The pragmatic validity of moral pluralism. In Advances in Experimental Social Psychology(Vol. 47, pp. 55-130). Academic Press.
Hursthouse, R. and Pettigrove, G.: Virtue Ethics, SEP (Winter 2018 Edition), Edward N. Zalta (ed.)