More than two years after his studio was searched and Taiki Masuda (main picture) was arrested, the 29-year-old tattoo artist has had his first day in court. Standing before the Osaka District Court on April 26, Masuda declared himself to be innocent of the charges brought against him and said he "cannot accept" that tattooing a consenting customer is a crime.

The hearing was the first in a trial that Masuda demanded, rather than simply accepting a fine and closing his tattoo parlor. Arrested in 2015 in a police crackdown on tattoo parlors in Japan's second city, Masuda was charged under a "medical practice notice" introduced in 2001 in an effort to regulate cosmetic tattooing, such as permanent eyebrows that requires any such procedures to be conducted by a qualified doctor.

Masuda was one of around 30 people arrested in the sweep of Osaka's tattoo parlors, but was the only one to fight his corner. The others paid their fines and stopped their work, or moved to another part of Japan and started their businesses again.

'I cannot understand'

"I am not doing this for therapeutic purposes, so a doctor's qualification is not required," he told the court, the Yomiuri newspaper reported. "I cannot understand why this is a crime. I am convinced that tattoos are art, and I am convinced that a tattoo artist should be recognized as a profession," he added.

The next hearing in the case has been set for May 23 and the court is expected to hand down a ruling in late July. That is unlikely to be the end of the legal proceedings, however, as whichever side loses the first round is virtually certain to appeal the ruling to a higher court.

The prosecution claimed in its opening statement that tattooing "has a risk of injuring the skin and causing bacterial infections and allergic reactions." As a result, anyone who is not a doctor is carrying out "an act of causing harm" by tattooing someone.

Masuda and his legal team disagree strongly.

"The police charged 20 artists in this crackdown, but only Masuda decided that he wanted to take the case to trial," said Junpei Shirai, a member of his legal team. "The others all paid a fine and stopped, but Masuda refused to accept that what he was doing was criminal."

Shirai told DW that the defense will assert that prosecutors are infringing upon Masuda's constitutionally guaranteed right to a profession of his choosing and the right of a consumer to the pursuit of happiness.

Broader crackdown

The authorities' targeting of tattoo artists may be in part motivated by a broader crackdown on Japan's underworld groups, the notorious "yakuza," who are famous for their full body artwork.

"Tattoos have a long history in Japan but they do have a bad image and a stigma attached to them because of their association with the yakuza," Shirai said. "It may very well be that the Osaka police are trying to make a statement."

Yet Masuda's works are not the elaborate dragons and demons favored by gangsters, and he went to great lengths to ensure that his clients were not members of the underworld, while he also prided himself on the sterility of his equipment and facilities.

"Taiki never did any work on 'yakuza' and he actually required anyone going to him for a tattoo to sign a document saying they were not a member of an underworld group," said Hyoe Yamamoto, an independent filmmaker who has been making a documentary on Masuda for the last 18 months.

"Taiki and his lawyers feel that the prosecutors' claims are simply out of touch in modern-day Japan," Yamamoto said. "But it is a bigger issue than that; tattoos are associated with criminal gangs so how can Japanese society open up to them as something quite different."

Tattoos are still a rarity in Japan, although the influx of foreign tourists to the country in recent years has demonstrated the degree to which skin art has become a mainstream fashion statement elsewhere in the world. Still, visitors to public baths, swimming pools and other venues where a tattoo is revealed are invariably asked to cover it up with a plaster. If the tattoo is too large, then they are usually refused entrance.

"The Japanese government is calling on these establishments to open up to foreign visitors with tattoos and to be more liberal, but they don't say anything about Japanese with tattoos," points out Yamamoto.

Litmus test of society

"This case is becoming a litmus test of how open Japanese society is," he added. "We want Japanese society to have that conversation."

The case hinges on whether Masuda's arrest was legal and, if the court rules in favor of the prosecutors than that means that any tattoo artist operating in Japan is liable to be arrested.

At present, Yamamoto said, they operate in a grey zone; the police generally do not bother tattoo artists as long as they keep a fairly low profile. Should Masuda lose his case, then more local governments may decide that they will enforce a zero-tolerance policy.

And despite broad public support, Shirai is not entirely confident that his client's position will carry the day.

"He is an artist and I hope the court will recognize that and give a not guilty ruling," he said. "But you have to remember that 99.9 percent of cases that go to trial in Japan end up with a guilty verdict."