The Morning Person Paradox
Some people did cheat less in the morning, Sah found, but only if they were early birds to begin with. The opposite was also true: night owls cheated less in the evening. Time of day had less effect on honesty, the group concluded, than did the synchronicity between person and environment. “Our results should really dissipate those stereotypes of morning people being more saintly,” Sah says. “The important thing is the match.” Early birds aren’t ethically superior. And, to the extent that other research suggests that they are, it may just be that they are luckier: modern society, for the most part, is built around their preferences. We are expected to function well early in the morning. We can’t just wake up when our bodies tell us to and work when we feel at our peak.
Research suggests people who get up early are no more ethical than people who don’t, unless they are people who are going out of their way to get up early, which is something that can only be known by the sleeper himself. So, in conclusion: trust nobody, including morning people.