To me it depends on the situation. But I don't always like to make eye-contact. There are times when it's necessary, and times when it's not. By the way, it's not always possible to detect a lie by analyzing someone's eyes. If a person is a good liar, they will know how they look when they are telling the truth, and manipulate that. But in general, yeah. The eyes aren't the only indicators of a liar. Tone of voice, breathing rates, movements, etc. But most of these are very dependent on the person's personality... as is how one's eyes look during the act of a lie.