An Old Buddy Told Li Merit
Inspector Fu's mentor was named Li Qiao. He was a full Imperial Inspector and had been such for twenty-eight years at the time of his downfall. His family was from the Harbor of Fortunate Arrival, a second son from a middling sized merchant house. The money went to his elder brother, but much of the focus on the family served to provide him a well-polished education and place him high in the civil service.
His corruption, which came to light and resulted in his firing fifteen years ago, did not approach the level of true treason - he never covered up any serious malfeasance or great crimes, but he did line his pockets by blackmailing those who did not wish embarassing peccadillos or mistakes to come to light, many of which he discovered in pursuit of greater investigations.
A list is included of a number of the incidents he investigated, and of some of his blackmail targets.
It took some time to track down his current whereabouts - he now goes by the name Goan Niu, and lives in a small town north of the Port of Auspicious Voyage. He spent some years in a small trade business - he seems to have made it out of his firing with some money intact, which he used to build himself a decent nest egg, but is basically retired now, and spends his time drinking tea and gardening.