“Are you suggesting, counselor, that the mark on Mr. Prosecutor’s forehead is not a fact?”
In order for the defense attorney to prove prejudice, he would have to provide evidence that the ashes are prejudicial. Merely pointing out the fact that the attorney has ashes on his forehead is not evidence.
Let me try to clear up your confusion about "evidence." Ashes on one's forehead are evidence that one attended Ash Wednesday mass during one's lunch break. The issue is whether evidence that one attended Ash Wednesday mass during one's lunch break is admissible to a jury. It is not under Rule 403.