This is an important discussion. The Evo Sith will tell creationists to stifle themselves when they point out the flaws in evolutionary thinking and the bad science involved. We are "not qualified", they say, and demand that we produce some kind of educational or professional qualifications, as if they were some kind of discussion police.
When coached in debating tactics (the object is to win, not to discuss or actually learn something), atheists and evolutionists are actually encouraged to use logical fallacies like this. (That is, demanding credentials is not only an ad hominem, but a red herring.) This is supposed to get the creationist defending himself, or discussing the foolishness of needing qualifications, rather than to discuss the actual point at hand. Bluntly, it is a feeble attempt at silencing the opposition.
It is also a double standard. Evolutionists will require some arbitrary "qualifications" for Darwinism deniers, but they are usually lacking in substantial education themselves. In addition, this often leads to the ad populum fallacy of "Most scientists believe evolution".
The following article shows the absurdity of making such requirements of creationists, and goes into detail, raising some very interesting points.
A common quibble laid at the feet of the creationist is that he/she is not qualified to speak about scientific matters relating to the creation/evolution controversy. For instance, Mark Isaak, the editor of The Index to Creationist Claims, stated that “for every creationist who claims one thing, there are dozens of scientists (probably more), all with far greater professional qualifications, who say the opposite” (2005, emp. added). Others assert that creationists make “the elementary mistake of trying to discuss a highly specialized field…in which they have little or no training” (Holloway, 2010). Do these assertions have any merit?
First, such assertions are ironic in light of other statements by some in the evolutionary community. For example, in the “General Tips” section of the article, “How to Debate a Creationist,” the Creationism versus Science Web site tells its followers,I encourage you to read the rest of this enlightening and challenging article, "You Creationists Are Not Qualified to Discuss Such Matters".
you don’t need to become a qualified expert [in relevant evolutionary subject matters—JM]…but you should endeavour to know as much or more about these subjects than your opponent does (which is often a surprisingly easy task, since most creationists learn only the barest superficialities of any given scientific principle before feeling confident enough to pontificate on it) (2007, parenthetical item in orig., emp. added).It seems that some do not wish to hold all participants to the same standards. It is clear that the author wished for his audience to be able to win a debate, rather than consider the validity of the arguments being posed by creationists.