Depends on where these lies are made ? and what is their impact ??
If it is at the personal life level and with no impact on business on on the job/role this liar is handilng, then I have nothing to do except an advice ... and I still do NOT like this behavior ... for sure.
If it is at the professional level and has an impact on business and/or on the job/role this person is handlign, then the system will deal with him/her in light of such impact/damage caused by this behavior