Ring of Gyges: Justice when no one's looking?

VIDEO INTRO: https://www.youtube.com/watch?v=bxt93qqJoiw (1m21s)

The Ring of Gyges is a story about a powerful ring that could make you invisible (long before LOTR) and able to get away with anything. If you had it, would you be just and be ethical with it? Could people really resist the temptation to be immoral, when they can get away with anything?