403 is Federal not Iowa and the term substantially is as high a standard as compelling. I did not adequately express the meaning of absolute. It was not in reference to the potential for predjudice but in terms of two rights in coonflict. There may, in some undetermined manner been an effect on the trial, but there was an absolute denial of a Catholic’s right to freely practice his Faith. You cannot absolutely deny a right because to practice it MAY have some effect on another right. I return to the point of observant Jews in court. They are never denied the right to observe the requirement to wear yarmulkes. That is as much a symbol as ashes are for a Catholic.
That's not accurate. Just like in cases of hajibs, Crucifixes or crosses, there are dozens of cases wear judges have instructed either witnesses or attorneys to remove yarmulkes. These instructions, to my knowledge, have never been found to be reversible error by appellate courts.
The fact of the matter is that the trial judge has historical been given tremendous latitude when setting standards for dress in his/her courtroom. Appellate courts have been hesitant, even unwilling, to question the primacy of the trial judge's discretion in these matters.
If the trial judge believes that such adornment may be prejudicial in some way for the particular case he's adjudicating, the appellate court has typically acquiesced to the trial court's judgment.