Set aside the fact that we are not dealing with a supernatural agent about which we know nothing, but with humans that we understand well. Let's look at how the court actually reached its conclusion.
Publius explains in Justice Thomas and Racial Discrimination (my emphasis):
To be grossly general, the Court based its decision on the following: (1) peremptory strikes were used to exclude 91% of eligible black jurors; (2) during the “whittling,” black and white jurors were asked different kinds of questions about the death penalty; (3) prosecutors claimed to strike black jurors for reasons that applied to white jurors they kept; (4) the prosecutors “reshuffled” the order of jurors to be considered when black people were at the front of the list (it’s a rather obscure procedure, but quite damning); (5) a recorded history in that prosecutor’s office extending into the 1970s of an official policy of excluding minorities from jury service (it was written in a manual, though the policy had ostensibly ended in the late 1970s).
The big point, though, is that the evidence in Miller-El is about as obvious as these cases get. If this isn’t enough, then nothing is (short of an open confession).
Now Nelson claims that items 1 and 4 on Publius's list are proof that the Supreme Court is relying on IDC style logic. And I think that, knowing people, it might be reasonable to use these statistical analyses alone (after all, we know that intelligent agents are involved!).
But the Court also saw a clear difference in how the two racial groups were handled both in terms of questioning, and in terms of the consequences of the questioning, and the Court saw a manual which we know was written by a supervisor which instructed the prosecutor to act this way.
Here's another pass at the real story. In order to establish racism, the guy on death row had to show that the prosecutor intended to skew the jury's racial mix for explicitly racist purposes and that he did so. The first item shows that the bias was introduced beyond some level of statistical certainty (that's what Nelson gets all excited about). Then the inmate had to show that the prosecutor used his intelligence to effect that shift, which is what items 2-4 do (the shuffling is interesting, but only if you know an intelligent agent is involved). The last item shows the intent, without which, there's no game.
IDC, by contrast, cannot show that any supernatural designers exist, nor can they offer any insight into that designer's (or designers') intent. They get to the first item (event x is very rare) and give themselves a pat on the back.
“Sucka Nigga” by A Tribe Called Quest from the album Midnight Marauders (1993, 4:05).