The committee should not be meeting to hear reasons from you why you want to wear a kilt. I should be meeting to determine if there are any objections to your wearing the kilt and whether those objections have any merit. A kilt is considered a formal, semi-formal, dress and casual item of men's clothing. Just because a supervisor doesn't like it is not a valid reason. Is he/she going to ban the wearing of colors that he/she dislikes?
But don't be surprised if you are turned down. If there is a committee you can bet they have already met and have had discussions on the subject and will have made up their minds before you walk into the room. Having you meet with the committee is a CYA move in case the discrimination issue arises.