O you who have believed, be persistently standing firm in justice, witnesses for Allah , even if it be against yourselves or parents and relatives.
Whether one is rich or poor, Allah is more worthy of both.
So follow not [personal] inclination, lest you not be just.
And if you distort [your testimony] or refuse [to give it], then indeed Allah is ever, with what you do, Acquainted.
[Qur'aan 4:135 - Translation Sahih International]
Speak the truth, and do not fear the people.
It has been reported that the Messenger of Allaah (sallallaahu alayhi wa sallam) said:
The fear of people should not prevent anyone of you from saying the truth when he sees it, witnesses it, or hears it.
The wording in Ibn Maajah is:
The fear of people should not prevent a person from speaking the truth when he knows it.