打草惊蛇(da cao jing she)
Beat the grass and the snake will be startled
Premature actions which put the enemy on guard
Once upon a time, a county magistrate named Wang Lu worked in present day Anhui province, Eastern China. Wang Lu was a greedy magistrate who took many bribes. One of his secretaries was equally corrupt, and who even regularly assisted Wang Lu in his deeds.
One day, a man went to the magistrate to lodge a complaint against the secretary to accuse him of the same crimes as those that the magistrate himself had committed. Wang Lu was so shocked and frightened that he was not in the proper state of mind to handle the case. Instead of issuing a judgment, he could not help but wrote these words: "Wahlao! Do you know that by beating the grass, you are scaring the hell out of me this a snake under the grass?!"