A mute is a form of damage control, used by in-game Player moderators, as well as a form of admonition used by Jagex moderators, and Customer Support to those who are guilty of breaching the hardest-weighted Rules of Conduct.
Permanently muted players are unable to speak freely to other players.
A player has been temporarily muted.
Support for Mutes
Mutes are a way of stopping any more damage from being done by the rule-breaker. In some cases, these rule-breakers may not have been aware that they were breaking the rules, so a mute actually may save that player from being reported possibly hundreds of times and getting blackmarks for each reported breaching of the rules. Mutes given out by player moderators can last up to 48 hours, just long enough for Jagex to investigate the situation or longer if Jagex deems that it is necessary to do. Many permanent mutes have been reported to be given up after a period of one year. Muted players are also barred from posting on the Runescape Official Forums.
In-game repercussions
After the Offence System Update, a pillar shows what zone of offence you are in. The text displayed when either given a 48 hour mute by a Player Moderator or the automated mute system from the spam filter is also shown.
A muted player will not be able to talk in-game (except through quick-chat) or on the forums, however, they can still play the game as usual and trade with other players. Muted players usually communicate with others by using emotes, Quick Chat or external forms of communication. If a player is on his or her last chance, and they commit an offence, they will be permanently muted or possibly permanently banned. Also, if a player is muted for website advertising or real-world item trading, the player may become banned by Jagex right away. Mutes may be appealed if the player is past the green zone.
Quick Chat
Since 21 May 2008, muted players are able to communicate with others in the game, to some extent, by using the Quick Chat system, so being confused with macroers does not happen anymore (note: Modern macroers commonly use quick chat responses similar to the way a chat bot does, so muted players are again mistaken for bots frequently.). However, there is no option on Quick Chat to inform other players that they are muted. However there is an option that says "I can only use Quick Chat."
It is currently not possible to mute players completely; some muted players keep repeating a random Quick Chat line with F11, annoying the others. Reporting this is not useful, since the players can't be muted any further.
Mute Abuse
A hidden update was added to the game, where players that said the name of a prolifically advertised gold-selling site in one or two lines would be automatically muted for 48 hours upon log out. This was later removed due to players tricking others into saying it to get them muted.
As of September 18, 2012 the auto-mute returned, and advertising bots get auto-muted for some minutes. After getting muted several times they play a choking animation and get banned.
Criticism
The mute system has faced criticism from players for perceived flaws and issues. Among these are that player moderators are able to immediately mute players for up to 48 hours, even with insufficient or no evidence to support the mute. Additionally, players have pointed out problems with the appeal system, citing long appeal processes that sometimes take longer to resolve than the mute's duration.
Before the offence system update in May 2009, players with perfect or near perfect records who received minor mutes were not even given the chance to appeal the mute. The appeal would be deferred until a more serious offence was committed. There are still occasions where muted players are not able to appeal their mute, by having the committed offence not listed so the appeal option can not be done.