What "rather large group of scientists"? I hear all the time about these supposedly growing group of scientists who don't think there is an antropogenic global warming, but their research output seems to be nil. Also, when they talk about such group (like the famous 650), it always appears that most of those scientists have no scientific credentials related to the topic.
There are no global-warming skeptic scientists. There are scientists, period. And scientists have to be skeptic. But surprise! skepticism also includes acknowledging what data says. Some scientist obtain data that is inconsistent with one or more of the suppositions and conclusions of an AGW, and of course, they have to defend their data, because that helps reaching the truth. Nevertheless, most of the published research on climate change is consistent with the IPCC scennario.
Let me tell you a story: once upon a time, continents were thought to be stable. Then came Wegener with is continental drift hypothesis, and he seemed to be right, but the mechanism didn't make sense physically, so it had to be discarded. Eventually, the good mechanism was discovered and Plate Tectonics theory was developed. It gained momentum thanks to all the research and testing verifying it, and it seemed to be the truth. Nevertheless some scientists didn't like it, didn't think it could work. Being in the minority and against a theory that has experimental support means you could well be wrong, but being wrong isn't a sin in science: it happens all the time. But this is what separates scientists from crooks: while many of the tectonics-skeptics were embracing the crudest pseudoscience, others were making good science. Defending the wrong option, their contribution was still very valuable because it found the weaknesses that Tectonics had, and helped to get closer to the truth.
Scientists who publish data that doesn't fit in current mainstream of climate modelling is of extreme importance. Researchers who find weaknesses and faults in the AGW are making a great service to science and to the knowledge of the AGW itself. But the evidence isn't majoritarily with them.
On the other hand, we have the crooks, in both sides obviously. But being a crook who is in the side of the facts merely makes you a shady maneuverer. Being a crook against the facts makes you, and the people who manage to bias to you, the laughing stock.
About George Washington University.... well, maybe it's respected nationally, but it ranks pretty low worldwide:
http://www.scimagoir.com/pdf/sir_2009_world_report.pdf
I mean, it ranks even lower than my university XD (385 vs 408)!
(Dang Noam Chomsky worshippers...)
I guess it's because of their emphasis on teaching.