It is narrated from Hazrat Abu Saeed Khudri (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: The awe, fear, and grandeur of people should not prevent any of you from speaking the truth when he sees it himself, witnesses it, or hears it.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 11428