Interesting! 

Here's a take on narcissistic sociopaths:

"Truth does not mind being questioned but a lie does not like being challenged" - forgot who said that

A vulnerable narcissist for example (as opposed to a confident one) will lie to you as a tactic to avoid feeling insecure.

If you believe the lie they told you then they outsmarted you. If you don't believe the lie then they feel justified in playing the victim. Their inner dialogue is usually some bullshit about how they feel things more deeply than others therefore their actions are justified somehow. (Cheaters often think in this way) 

On the other hand a confident narcissist wouldn't give a fuck if they're caught in a lie. (Jada Smith for example)