In what circumstance would lying be okay according to virtue ethics?

When you have some bad news and you don’t want to ruin someone’s mood.

The sky is green, the grass is red. Is this lie such a bad thing? This type of lie would be allowable according to virtue ethics.

Lying is OK in order to save a life.

Lying is never really OK. It can be justified when it is a lie to spare someone’s feelings or as @gondwanalon says to save a life.

I think you will appreciate this article by Steven Pinker on morality from a psychological and biological viewpoint. One particular point of interest: is that we act first and provide moral justifications afterwards.

The article mentions five broad categories of moral attitudes given by Jonathan Haidt – “harm, fairness, community (or group loyalty), authority and purity”: Liberals and conservatives differ in the emphasis placed on the various categories. Interestingly, lying does not fall directly into any of those them, but a particular act of lying can fall across several of them. Perhaps the idea that lying is wrong in and of itself would fall into the area of purity.