The virtue ethicist believes it is bad to be in a habit to lie because being predisposed to lying is opposed to the virtue of the truth. We've all known people who lie by habit and they are unpleasant and vicious to be around. I don't know if most virtue ethicists (who don't also fall into the natural lawyer camp, below) would say it is per se bad to lie, but most would say it is vicious.
The natural lawyer believes that speech has as its natural end telling the truth and therefore it is contra naturam to lie. See the almost-impossibly-extended discussion here, for that: https://www.newadvent.org/cathen/09469a.htm
For all of these groups, there has variously been admitted something like an "equivocal statement"---a statement which has some interpretation that is technically true, but not the interpretation that the speaker knows will be taken by the listener as a falsehood. For example, my friend invites me out on Friday and rather than saying I'd rather be at home, I say, "I have something going on that night." He takes it to mean that I have other plans, but I don't. But technically, breathing is "something going on" so I haven't lied. (Whether your social relationships will stand your doing this is another matter ;))
I'm personally fall in something like the virtue ethicist camp, but I do believe sometimes, in justice, a lie must be said, and not all of those situations can be covered by an equivocation.