Now, deborah roberts with more of "20/20" too good to be true. So help me god. Congratulations, mr. President. Reporter: It was the talk of the week. The presidential inauguration. But believe it or... See More
Now, deborah roberts with more of "20/20" too good to be true. So help me god. Congratulations, mr. President. Reporter: It was the talk of the week. The presidential inauguration. But believe it or not, some people were reacting to the swearing in even before it happened last week. That's when jimmy kimmel's "lie witness news" put some ped december treons on the spot. We asked people what they thought of the inauguration even though it hasn't happened yet. There's no way they could possibly have an opinion on it but that didn't stop people from having them. I turned the tv off. It bored me. Did I like when they threw teddy bears in the crowd? Yeah. Did you enjoy the tap routine? It worth it. Reporter: Politics is one thing. But what about a natural disaster? Today we asked people to describe what the earthquake that did not happen. It was real shaky. We had to dive underneath the table for the table. I felt so scared. Reporter: Were they confused, makes things up? Dr. Lillian glass, currently writing a book called "body language of liars" says don't be. We all lie. If somebody tells you they don't lie, they're lying. People lie to make themselves look good. They don't want to be the one that doesn't know the news. Reporter: In fact she says lying is kind of natural primitive behavior. For us humans, it begins in the cradle. An infant will cry and carry on, and then when they understand that the mothers come in, they hear the footsteps, they'll stop crying. And then if she doesn't come, she'll start -- the baby'll start crying again. Reporter: As we age, it gets carried on. Remember "mean girls" which captured the treacherous teen years? That the uglyiest skirt i have seen. Reporter: And of course in adult life, fibbing happens all the time. But mostly it's white lies. It's easier to, to tell a little lie than it is to get into the truth. Reporter: Sasha brown worsham, an editor at the website cafemom.Com, admits she's a natural at bending the truth. How good are you at lying? Pretty good, it's, I mean, it's pretty automatic. It, like, like that. Honey, I need to get you guys dressed. Reporter: She even allowed us to hang with her at home. For an exercise in "spot the lies." Play room? It's freezing down there. Reporter: Lie number one - he doubter wants to go to the play room. But her mommy doesn't. The snowman project is due today. Reporter: Lie number two. It's due next month. Here comes number two, over a toy. You are allowed one in your pocket or two. I was making up a rule where it fit in the pocket. No, they don't need to fit in your pocket. Reporter: And sasha is not just for the children. She writes about the five lies she tells her husband. Like, it was on sale or you look great. I sort of think of it as being kind. I want to make him feel good, if it's not true. You tell a husband what he needs to hear because it makes the marriage easier. Reporter: This author says that women are skilled at little fibs all to keep the peace. How often do women lie to their partners about how great they are in bed when maybe that's not quite the truth? Fairly often. Because it just makes it a better relationship. Reporter: Men lie too, just as much. But about different things. Women lie about their age and weight. Men lie about their height and how successful they are. Reporter: This blogger shows what the women lie about. I never go tanning. This is my real hair. What is wrong? Nothing. Reporter: And channels her inner guy to tell lies. I can bench 550 pounds easy. We are not lost. We are take a different way you don't know. I only hooked up with two guy girls. Reporter: With all the lying, can you spot the truth. It's not hard. We know what to look for and what to listen to. Eyes may blink a lot. A person my scratch themselves, bite their lip. Is their voice dying in the end of sentences. Even though you are a great liar, the truth does leak out. Reporter: We wouldn't have to worry about that if we just lie off the lying. Do you think we could do it? I think we could do it. It would make life complid. But I could -- do an entire truth day, absolutely. Reporter: Can I believe ♪
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