  Calling a Stag a Horse 指鹿为马

  In the Qin Dynasty, the prime minister, Zhao Gao, plotted to usurp the throne. Fearing that the other ministers would oppose this, he thought of a way of testing them. He presented a deer to the emperor, and said, 'This is a horse.' The emperor laughed, and said, 'You must be joking; this is a deer.' Then Zhao Gao asked the ministers present. Some kept silent, some agreed that it was a horse, and others said that it was a deer. Later Zhao Gao had all the ministers who had said that it was a deer killed. 
  秦朝丞相赵高想篡夺帝位，怕群臣们不服气，就想了一个办法来试一试大家。他牵来一只鹿献给皇帝说："这是一匹马。"皇帝笑着说："丞相你弄错了吧？这是一只鹿。"赵高就问旁边的大臣们。他们有的不做声，有的跟着赵高说是马，也有说是鹿的。凡是说鹿的人，后来都被赵高杀了。从此以后，群臣都害怕赵高。

  This metaphor describes distorting facts by calling white black.
  "指鹿为马"用来比喻故意颠倒黑白，混淆是非。