Something I've been curious about relating to this topic, what do you do in a situation where an ex-employee (or ex co-worker) is lying about their position with the company?

Are you allowed to sue for misrepresentation (if such a thing exists) or is it pretty much deal with it? For example someone claiming to have been with the company for a year longer than they really were in a role they never held (eg: someone working in customer service at Facebook from 2008 - 2009 then claiming on their resumé they worked in the engineering department from 2008 - 2011).