Hmm... now I do have to get into that discussion of semantics. Stuartvine, I believe, is talking about something quite different, fraud. I think (although I may be wrong) that the OP was writing about stringing, albeit an extreme kind, which seems to me to be quite different.
Stringing: The observer gets a poor view of bird, makes a decision to "call" the bird anyway, and (usually) chooses the rarer/more spectacular possibility. (Ex. #1- I'm on Lake Ontario, and get a fly-by view of a distant, small merganser, which I identify as a female Smew; after all, one was reported by competent observers in the area last week.) Wishful thinking is involved, and maybe some incompetence, but not fraud - the observer sincerely believe in his/her I.D.
This kind of thing happens all the time; knew a perfectly honest fellow who once claimed a flock of 22 Am. Wigeons on the local Christmas bird count, despite the fact that (a)he couldn't document the plumage and (b) our yearly average for the species, over 65 years of annual counts, is right round about zero.
Fraud: The observer sees something common (or perhaps nothing at all), and decides to grab some attention to his- or herself by claiming something rare/spectacular. (Ex. #2- I'm doing a bird race, and want to fluff up my total a bit; I tick Smew, because I know one has been sighted in the area recently. If pressed, I produce a photo of one I took on vacation in Europe last year.) This is truly odd behaviour, which I have read about, but can't think of single case of I've come across myself.
I've always thought that the difference between the concepts is quite clear-cut. Reading this thread, I'm now starting to think there might be a bit of bleeding from one into the other. As in: a stringer could conceivably cross over into fraud to support a sincerely-held belief. An example might be an observer who strings a rare bird, but produces an image as evidence an image that is not the actual bird in question, and lies about the origin of same. The intention, in the mind, is what makes this different from case #2 above; the birder in this case is still stringing, according to my definition of the word, but committing fraud only with regard to the evidence.
TTFN,
Peter