How do I prevent non-buddhists from going against fourth precept?

As we know fourth precept is the one precept that the Bodhisatta has never said to have broken since he started cultivating Paramita. When I need to prevent a Buddhist person form lying, I state the above statement. And that is the reason that I was also prevented by telling lies. But if we need to prevent a non-Buddhist person from telling lies or going against fourth precept, how can we do. How can we motivate him/her not to lie?