The viewing audience will not countenance being fooled

Fox

Former contestant Stacey Stillman filed a suit in February saying producers pressured two other players to vote her off the game, ahead of retired Navy Seal Rudy Boesch.

CBS has counter-sued Ms Stillman, accusing her of defamation and breach of contract.

In its suit, Fox cited Ms Stillman's action in alleging that CBS and the makers of Survivor has engaged in "prearranging and predetermining the outcome" of both the original Survivor and its sequel, Survivor: The Australian Outback.

Fox said they did it to "appeal to a desired audience and obtain a particular outcome".

Fox also referred to media statements attributed to two other former contestants and used in Ms Stillman's suit.

Gretchen Cordy and Jenna Lewis are quoted as saying producers influenced contestants behind the scenes.

'Monopoly'

"[This conduct] endangers the entire industry...because the viewing audience will not countenance being fooled into watching a purported reality competition where the outcome has been fixed."

The contestants on Boot Camp do not sit around starving, trying to catch bugs or fish

Fox

Fox added its own reality TV show, Boot Camp, was not fixed.

The copyright suit against Boot Camp was part of an attempt by CBS to "seek a monopoly over reality television game shows" by intimidating rival broadcasters "through baseless litigation and threats".

Fox disputed the claim that Boot Camp copied the Survivor format illegally.

"The contestants on Boot Camp do not sit around starving, trying to catch bugs or fish.

"The recruits on Boot Camp undergo a mentally and physically challenging conditioning that is the core of life as a Marine recruit."

This week Survivor executive producer Mark Burnett admitted that he used body doubles to re-enact some parts of the show to get better camera shots.

CBS has not yet commented on the latest lawsuit.

A British version of Survivor, fronted by ITN journalist Mark Austin, will start on ITV later this month.