It is narrated from Hazrat Abu Saeed Khudri (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: On the Day of Resurrection, every deceiver will have a flag at his buttocks in proportion to the extent of his deceit, and there is no deceit greater than the deceit of a ruler.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 11427