Moving the goalposts
"Moving the goalposts" is a British expression first popularized in the late 1980s and 1990s and is obscure in America outside of use by evolutionists in debates. It has only 47,900 references on a Google search as of June 30, 2010, over 10% of which show up when searching "moving the goalposts" and "evolution".
It is an expression used as a substitute for giving a direct answer to a question, on the pretense that the questioner is changing his argument.
As evolutionists are incapable of explaining the wonders of Creation, they often resort to this phrase when pressed by creation scientists in debates, as in "now you're moving the goalposts" in response to a question. Thus, asserting that someone is moving the goalposts is a common logical fallacy.