Photo/Illutration This application used by a Tokyo senior high school states the student is submitting it to receive certification that his or her natural hair color is other than black. (Momoko Ikegami)

A hair color code is being strictly enforced at close to half of all senior high schools operated by the Tokyo metropolitan government.

Students who turn up to classes with wavy hair or locks that are not uniformly black are required to submit a document signed by their parents or guardians stating that it is their natural look.

The policy has been adopted by more than 40 percent of such schools in the metropolitan area, according to Japanese Communist Party members of the Tokyo metropolitan assembly who questioned the edict.

The issue of school regulations covering hair color is one that has come before the courts and stirred international interest in the rigid system that governs Japanese schools to encourage conformity.

The JCP, sensing the issue infringed on human rights, submitted an information disclosure request and was rewarded with a pile of documents turned over by the Tokyo metropolitan board of education.

Of the 177 metropolitan senior high schools for full-time students, 150, or 84.7 percent, had some form of regulation regarding hair. Seventy-nine schools, or 44.6 percent of the total, asked students to turn in documents signed and sealed by their parents certifying that they were born with a natural wave in their hair or a color other than black.

According to the documents, some schools even asked for photos of certain students when they attended elementary or junior high school to confirm the veracity of the details provided. In other instances, students were required to provide documents from their doctors backing their claims about the natural state of their hair.

Some schools invalidated the documents if the student had even once dyed his or her hair or had a permanent at a hair salon.

Some schools used a color scale so students could grade their hair color.

Education board officials insisted the documents were needed to avoid situations where teachers reprimand students about their hair based on misperceptions.

They added that notices had been sent out to individual schools asking that they explain to students and their parents that submitting the documents was entirely voluntary.

However, a study by the JCP bloc in the Tokyo metropolitan assembly found that only five senior high schools had made a point of stating that this was the case.

“Registering the hair color of a student is a human rights violation similar to asking them to register their skin color,” said one JCP member. “It is a natural right to have the hair the student was born with and it is not something that has to be approved by others.”