Walter T. Brown is an engineer, young earth creationist Kent Hovind-style, and director of his own ministry with the Orwellian name Center for Scientific Creation (which seems to consist of Walt Brown), for which he works full time as a ”researcher”, writer, and speaker. According to his self-published book ”Compelling Evidence for Creation and the Flood”, Brown has a Ph.D. in mechanical engineering from MIT, and he may be considered one of the leaders of the creation science movement (this excellent overview over the creation movement at least awards him a relatively prominent place).
In 1998, Brown was appointed to a committee reviewing Arizona's state science standards, but despite his attempts he failed to remove evolution from the Arizona state science standards.
His main publication is his already mentioned book ”In the Beginning: Compelling Evidence for Creation and the Flood,” in which he argues for flood geology, claims that the works of other scientists does not support evolution (which, as expected, is primarily based on misrepresenting them), and attempts to explain parts of reality that fits poorly with the Bible (astronomy, for instance). His general strategy is to argue that moderen science cannot explain these astronomical and geological phenomena, even though it can, and that therefore goddidit. Some criticism can be found here. His ”20 questions for evolutionists” are dealt with here, and his own claim that evolutionists refuse to debate him, therefore he is right, is dealt with here.
Brown’s primary positive contribution is his hydroplate theory – according to his bio he learnt some geology after(!) developing the theory – which is remarkably silly.
Brown apparently maintains rather contentious relations with other creationist organizations; Answers in Genesis has a standing offer to Brown to publish some of his material in their ”journals”, though Brown has thus far declined; the old earth creationist organization Answers in Creation has published material rebutting Brown's hydroplate theory, on the other hand, and The Christian American Scientific Affiliation (which doesn’t seem to be creationist) has debunked Brown’s video ”God's Power and Scriptures Authority”.
Bob Enyart’s bulldog, the incredibly dense and dishonest Will Duffy, thinks Walt Brown is one of the greatest scientists ever, and Brown is taken to be an authority on evolution by Conservapedia despite his complete lack of competence or training in the field, and anauthority on astronomy by others, despite his rather startling lack of even minimal understanding of the field. The WND has uncritically published some of his nonsense, such as his claims that Noah’s flood created the asteroids and comets in the solar system (discussed here).
Diagnosis: Babbling beefhead and denialist whose main techniques are, as one would expect, ignorance, misrepresentation, goddidit, and – if everything else fails – appeal to ”worldviews”. He may not be the most influential creationist out there, but is often pulled out by the densest members of the creationist movement and probably does have some negative impact on the world.