Jeong Cheol
Jeong Cheol, famous poet and head of the Western faction, was in charge of investigating the case and used the case to effect widespread purge of Easterners who had slightest connection with Jeong Yeo-rip. According to Easterners' accounts, Jeong Cheol tortured even 80-year-old mother and 8-year-old son of Yi Bal, leader of Eastern faction. According to Westerners' accounts, Jeong Cheol tried heroically to save Yi Bal and Choe Yeong-gyeong from Seonjo's wrath. In any event, 1,000 Easterners were killed or exiled in the aftermath. It is also believed that Seonjo used this incident to weaken the Sarim's power.