How do you know someone is lying to you?

Determining if someone is lying to you is very similar to the research process. If you have the a feeling someone is lying to you, you often will establish research questions. For instance, why would this person be lying to me? What would they be lying about? Why are they hiding what they are? Once these questions are established one might look for previous "research" such as past experiences of this person lying or other peoples experiences of this person lying. Once a basic understanding about the personal past history of lying is established new questions might be added and it is time to begin ones methodology in discovering if the person is lying. One would begin collecting and gathering date maybe through a "interview" or one on one talk with the person about the topic of the lie. Or maybe researching facts related to the lie such as people that might have been with the person or seen something. Once all the data is collected about the person and the lie it is time to come to conclusions. Most of the time through this process one can determine if the person is lying and have evidence to back this belief. In this regards, the process of determining if someone if lying is very similar to the research process in qualitative research topics.