Last week's disclosure of extensive fraud by one of Japan's leading archaeologists has led to renewed soul-searching about how much the nation's more prominent scientists are allowed to escape criticism by their peers.

Here's one I found earlier: archaeologist Shinichi Fujimura with one of his finds. Credit: MAINICHI NEWSPAPERS

The self-examination began after journalists from Mainichi Shimbun, one of Japan's leading newspapers, twice filmed Shinichi Fujimura burying stone tools he had collected in previous archaeological digs, to unearth them again as prehistoric records. Archaeology is a national obsession in Japan, and Fujimura's 'discoveries' had often made front-page news.

Fujimura — who, according to critics, had no advanced degree and little scientific training — was last week sacked from his post as senior director of the Tohoku Paleolithic Institute. The episode has raised questions about a scientific culture that allowed Fujimura's work to continue, and to be taken seriously, despite suspicions that, it now emerges, stretched back many years.

“In Japan, it is hard to criticize people directly, especially those in established positions, because the critique is taken as a personal attack,” explains Hisao Baba, a palaeoanthropologist at the National Science Museum in Tokyo. He hopes this episode will help usher in a culture of research in which criticism is accepted at a scientific rather than a personal level.

The problem has been widely noted in Japan. A visiting physicist, for example, confided that he felt pressure to tone down research that overturned a leading Japanese physicist's findings as it would have been considered a “personal insult”.

According to Shizuo Oda of the Tokyo Metropolitan Division of Cultural Affairs, this soft-pedalling can make researchers as limited in their views as “a frog in a well that is unaware of the ocean”. Academics may not care about other researchers' work, or about having their own work peer-reviewed. This is especially dangerous in an archaeological community where, Oda says, intuition is sometimes valued over facts.

Fujimura claims that all the work he did before the filmed forgery was authentic. But most Japanese archaeologists are waiting for the rest of his findings to be discredited. Several archaeologists and anthropologists are now saying that Fujimura's discoveries did not mesh with other information about the sites. His discoveries suggested that the Japanese Stone Age stretched back as far as 700,000 years ago. But Oda has long held that there is no evidence of stoneware use in Japan before about 50,000 years ago.