 Their numbers increased to around 14,000 in three years.In 1393, the Hongwu Emperor reduced the Jinyiwei's duties after they allegedly abused their authority during the investigation of a rebellion plot by Lan Yu, in which about 40,000 people were implicated and executed.When the Yongle Emperor ascended to the throne, he was afraid that his subjects might be discontented with him, because he came to power by usurping his nephew's throne.