Referee
A referee is the person who can decide what the result of a game is if the players cannot agree.
In most tournaments this role is played by the tournament director or one of their assistants, but in major games the referee is only involved with one game.
From a referee you can expect in depth knowledge of the rules
There are many famous referees’ decisions and they are have often been contested, especially if there was misunderstanding about the rules of the game.
It is interesting to know if under tournament rules? the referee is passive (only act if asked) or active (can also act without being asked)
Under Japanese rules only the referee can decide that a game is void or no result because of a recurring position. But I (Willemien) am not aware if it has to be claimed by a player or not.
Other rules also allow referees to decide the outcome. An example in CGOS: the referee program decides if its superko rule is broken. without any player having to claim it. Maybe this is because it is a computer go tournament and the Go Text Protocol has no standard claim routines.
See also
willemien just found this page missing. Maybe go-players don't like referees.