Grady McMurtry is a regular guest on Revelation TV, especially on The Q&A Show (with Revelation TV founder and host Howard Conder). Now, Revelation TV is a British endeavor, but McMurtry is American: he is the head of Creation Worldview Ministries in Orlando, which consists of one person in addition to himself. So, yeah – he is a minor player. But he has received some attention by being unusually ridiculous, even by the already dismal creationist standards.
Like most creationists, McMurtry likes to mislead his audiences about his credentials. He claims to be a “scientific creationist” and often presents himself as “Dr. McMurtry”, but his doctorate is from an unaccredited Bible college, and his BA and MA have nothing to do with evolution (his credentials are discussed in some detail here). And make no mistake: McMurtry has no idea what the theory of evolution actually is, and tends to refer to anyone who disagree with him on matters geology or astronomy as well as “evolutionists” (https://rationalwiki.org/wiki/Evolutionism). For instance, according to McMurtry “evolutionists say things are getting bigger, better, faster, smarter,” which is not really what the theory of evolution predicts. McMurtry also blamed the Virginia Tech shootings on evolution being taught, since, as McMurtry sees things, evolution teaches us “that humans had no more value than cats and dogs,” and makes people feel that way about themselves since morality is impossible if facts are facts: if evolution is true and “you have excess people, then you can just put them in a bag, throw them in the river the way you would too many kittens or too many puppies,” says McMurtry. McMurtry makes this mistake because he is stupid and unable to distinguish a scientific theory about how the world works from a moral theory about how the world ought to be. (I leave it to readers to assess his views about "excess" puppies and kittens and evaluate his character accordingly.)
Part of the problem is, of course, that McMurtry has no idea about what science is. Thus, McMurtry says things like “evolutionists do not have one single scientific proof that [the earth] is old,” being apparently oblivious that “proof” is an expression belonging to mathematics and formal logic, not science; scientists have of course ample evidence that the Earth is old. Apparently state politicians, who are not usually elected for their scientific literacy, are sometimes impressed with McMurtry’s work.
As with most “scientific creationists” his own method for supporting the inerrancy of the Bible is the exact opposite of a scientific method. Instead, McMurtry carefully follows the form of the Texas sharpshooter fallacy (centered on the inerrancy of the Bible), and selects evidence to support the dogma by the time-honored means of confirmation bias and motivated reasoning.
Of course, McMurtry doesn’t only reject the science of biology; geology has to go, too (there is a video of him trying to argue against plate tectonics, for those who are interested). It is probably little surprise that he is a climate change denialist, too, viewing climate change as a communist conspiracy and environmentalism in general as a type of “terrorism”: “I Dr. Grady S. McMurtry have been studying the Global Warming/Global Cooling controversy since the 1960s. […] I am completely convinced that the controversy is 100% politically motivated and not based on good science. The promoters of either view are either extreme socialists or extreme communists. Their sole primary purpose in promoting either view is to destroy Christian capitalism and replace it with extreme socialism/communism based upon the religion of Secular Humanism.” Of course, nothing in that statement, or anything else he has done, involves any discussion of anything resembling the science of the topic, any more than his discussions of biology do. There has, of course, never been any scientific global warming/global cooling controversy.
Trivia: Grady S. McMurtry is the son of Aleister Crowley associate Grady Louis McMurtry.
Diagnosis: Religious fanatic, who uses his religious fanaticism to fuel his astonishingly silly pseudoscience and science denial. Not an uncommon situation, and McMurtry is honestly a B-level celebrity as far as creationist celebrities are measured. But whatever his impact may be, it is certainly not for the benefit of mankind.