Netiquette Rule 9: Don't Abuse Your Power

There are people in cyberspace have more power than others. There are wizards in MUDs (multi-user dungeons), experts in every office, and system administrators in every system. 

Knowing more than others, or having more power than they do, does not give you the right to take advantage of them. For example, sysadmins should never read private email. 

(Source: Rule 9- The Core Rules of Netiquette)