I try to act the same way when I am watched and when I am not, to keep myself consistant. Told my kids that if they are not certain what they should do to wonder if they would do it when their grandmother was in the room too!
However, interestingly, group dynamic research suggests that people will also behave more aggressively when they feel as if it is being expected of them and they are being watched. I think this study just shows that human beings react as pack animals in a way, we alter our behavior to attempt to please the group or the person we see as in charge. And many people who do not have a strong personality and have examined and developed their own values can be easily influenced by other people both for the good and for the bad. And many people do not have a set of moral behavior that is absolute and will alter their behavior according to mood. A personal peeve of mine is that people just have not examined their beliefs and so one minute will hold a belief and another minute hold a completely contradictory belief and somehow they can just live with it. 
It is not that I hold unchanging values, it is just that I hate them to be inconsistant, I want to have good reasons for what I believe, not based on whimsy, mood or lazy thought patterns.