My essay on inferring the right to wear hat from the US Constitution, written for online course
The right to wear a hat is not expressly provided for in the constitution but it implicitly stems from several provisions of the Constitution.
First of all, the preamble of the constitution says "...secure the blessings of liberty", where liberty is not limited to national independence. It refers to the people's way of living in every aspect. The fact that the constitution, unlike many other countries of the time, does not require any certain religion or life style for being president, senator or representative implies that this liberty covers every aspect of life style, doubtlessly including the wearings. I emphasize on this aspect of freedom, because the most common barrier, if any, against wearing a hat or any other choice of wearing relates to religious concerns.
In connection with and addition to the foregoing argument, the first amendment expressly states that US ctiziens are free to exercise their religion and they have freedom of speech. Wearing a hat, may also be a way of expressing oneself's ideas. The more an individual wears different from the regular style the more protesting that person would look and that may be the point that individual is trying to make by wearing a particular type of hat.
The fourth amendment states that no person's properties can be subject to unreasonable seizure, which in practice results that a government officer must have to find the reason for disallowing the people from wearing hat; the individuals do not have to find a special reason to defend their immunity about wearing hat as a way of possessing a property.
The nineth amendment says enumeration in the Constitution, of certain rights, shall not be construed to deny others retained by the people. Given the fact that people were wearing hat even before foundation of the United States, and there is no express provision that later prohibited hats, people's right to wear hat was already recognized by the nineth amendment. So, it is a constitutional right to wear hat under the nineth amendment.
Also, according to the Declaration of Independence, as a major US constitutional text, people's unalienable rights include the right to life, liberty and the pursuit of happiness. In her or his way in pursuits of happiness, one may enjoy the right to do anything that makes oneself feel better, to the extent it exceeds to the same right of other people. Wearing hat may well be one of the ways to enjoy these rights in pursuits of happiness, if it makes the person feel better and does not harm the counter rights of other individuals or the public order.
In addition to the written sources of the Constitution, this freedom can be inferred from the precedences of the Supreme Court, which has accepted many right that were not clearly mentioned or even implied in the Constitution but commonly adopted by the states, such as right to free advocate. Considering the practice of the states all over the territory, Supreme Court would see this is a right practically recognized by all states, so it is already a requirement of the Constitution that does not limit itself with its own text.
Lastly, Abraham Lincoln, the iconic image of the constitution, and deliverer of the Getsyburg Address, used to wear stove pipe hat, so anyone in the country must be allowed to wear it!