The assessment of the biological age of children`s characters created in the convention of Japanese animation in forensic practice

Introduction: According to criminal codes of most Western countries, possessing, producing and disseminating of fictional paedopornography is a crime. In light of these laws, the shotacon/lolicon (popular and widely available Japanese animations or comic books showing minors in a sexual context) seems to deserve special mention. There have been several convictions for violations of these laws, however, the methodology of a depicted person’s age estimation is still unestablished. The aim of this study was to assess the suitability of anthropometrical prediction of age to the analysis of characters animated in the Japanese style. Material and methods: The metric (distance between facial landmarks) and non-metric (type of chin shape) features of 173 animated characters’ faces were obtained. Material was collected from 90 most popular Japanese anime series. Measurements were conducted in ImageJ software. The correlations of age and standardized measurements: en-ex, en-en, eye height, pu-prn, pu-sto, pu-gn were examined. The chin shape was described by three independent ‘judges’. Results and conclusions: Correlations for pu-prn, pu-sto, pu-gn and eye height in females and in all males were statistically significant. Age prediction was made using linear regression equations. Good prediction (± 1 year) was obtained for 44% males and 17% females. Prediction within the acceptable range (± 2 years) was achieved for 23% of males and 18% of females. In total, the prediction with an error of no more than ± 2 years was obtained for 67% of males and 35% from females, which is comparable to the results obtained in the study of real children. Moreover, triangular or rounded chin shape was significantly more frequent in boys aged 10–12 years, and square in older boys 16–18 years. Current research provides a basis for developing a methodology for assessing the age of animated characters. There is a need for further research in this area.