Travel.State.Gov recommends that you do not wear a hat or head covering in your passport photos because this can cause shadows and make it harder to identify you. However, suppose you wear a hat or head covering. In that case, you must submit a signed statement that verifies that the hat or head covering is part of recognized, traditional religious attire that is customarily or required to be worn continuously in public or a signed doctor’s statement verifying the item is used daily for medical purposes.