Shinpei's background as a former detective in Tokyo has indeed played a significant role in shaping his approach to solving mysteries on Hitogashima Island. His keen eye for detail, strong analytical skills, and understanding of criminal behavior allow him to methodically gather evidence, question suspects, and piece together clues in a systematic manner. These skills help him navigate through the complexities of the mysteries on the island and effectively work towards solving them. Additionally, his experience in law enforcement provides him with a unique perspective that enables him to anticipate the motives and actions of potential culprits, allowing him to stay one step ahead in unraveling the mysteries. Overall, Shinpei's background equips him with the necessary tools and knowledge to tackle the challenges posed by the mysteries on Hitogashima Island.