When you judge, judge justly.
That is the Islamic principle,
Also,
Refrain from making false claims and accusations.
Be prepared of consequences for false accusations.
Do not hide testimony if it is justly required.
All of the above apply to every human being.
Please rectify your title and post.
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سَمَّاعُونَ لِلْكَذِبِ أَكَّالُونَ لِلسُّحْتِ فَإِن جَآؤُوكَ فَاحْكُم بَيْنَهُم أَوْ أَعْرِضْ عَنْهُمْ وَإِن تُعْرِضْ عَنْهُمْ فَلَن يَضُرُّوكَ شَيْئًا وَإِنْ حَكَمْتَ فَاحْكُم بَيْنَهُمْ بِالْقِسْطِ إِنَّ اللّهَ يُحِبُّ الْمُقْسِطِينَ {42
005:042 Khan
:
(They like to) listen to falsehood, to devour anything forbidden. So if they come to you (O Muhammad SAW), either judge between them, or turn away from them. If you turn away from them, they cannot hurt you in the least. And if you judge, judge with justice between them. Verily, Allah loves those who act justly.
إِنَّ اللّهَ يَأْمُرُكُمْ أَن تُؤدُّواْ الأَمَانَاتِ إِلَى أَهْلِهَا وَإِذَا حَكَمْتُم بَيْنَ النَّاسِ أَن تَحْكُمُواْ بِالْعَدْلِ إِنَّ اللّهَ نِعِمَّا يَعِظُكُم بِهِ إِنَّ اللّهَ كَانَ سَمِيعًا بَصِيرًا {58
004:058 Khan
:
Verily! Allah commands that you should render back the trusts to those, to whom they are due; and that when you judge between men, you judge with justice. Verily, how excellent is the teaching which He (Allah) gives you! Truly, Allah is Ever All-Hearer, All-Seer.
And whoever earns a fault or a sin and then throws it on to someone innocent, he has indeed burdened himself with falsehood and a manifest sin. Sura An-Nisa:112 (4:112)
Verily, We did send down the Taurât (Torah) [to Mûsâ (Moses)], therein was guidance and light, by which the Prophets, who submitted themselves to Allâh’s Will, judged for the Jews. And the rabbis and the priests [too judged for the Jews by the Taurât (Torah) after those Prophets], for to them was entrusted the protection of Allâh’s Book, and they were witnesses thereto. Therefore fear not men but fear Me (O Jews) and sell not My Verses for a miserable price. And whosoever does not judge by what Allâh has revealed, such are the Kâfirûn (i.e. disbelievers - of a lesser degree as they do not act on Allâh’s Laws). Sura Al-Ma'ida:44 (5:44)
And We ordained therein for them (The Jews): "Life for life, eye for eye, nose for nose, ear for ear, tooth for tooth, and wounds equal for equal." But if anyone remits the retaliation by way of charity, it shall be for him an expiation. And whosoever does not judge by that which Allâh has revealed, such are the Zâlimûn (polytheists and wrong-doers - of a lesser degree). Sura Al-Ma'ida:45 (5:45)
Let the people of the Injeel (Gospel) judge by what Allâh has revealed therein. And whosoever does not judge by what Allâh has revealed (then) such (people) are the Fâsiqûn [the rebellious i.e. disobedient (of a lesser degree)] to Allâh. Sura Al-Ma'ida:47 (5:47)
And so judge (you O Muhammad) among them by what Allâh has revealed and follow not their vain desires, but beware of them lest they turn you (O Muhammad) far away from some of that which Allâh has sent down to you. And if they turn away, then know that Allâh’s Will is to punish them for some sins of theirs. And truly, most of men are Fâsiqûn (rebellious and disobedient to Allâh). Sura Al-Ma'ida:49 (5:49)
Do they then seek the judgement of (the days of) Ignorance? (pre-Islam) And who is better in judgement than Allâh for a people who have firm Faith. Sura Al-Ma'ida:50 (5:50)
O you who believe! Kill not the game while you are in a state of Ihrâm [for Hajj or ‘Umrah (pilgrimage)], and whosoever of you kills it intentionally, the penalty is an offering, brought to the Ka‘bah, of an eatable animal (i.e. sheep, goat, cow) equivalent to the one he killed, as adjudged by two just men among you; or, for expiation, he should feed Masâkîn (poor persons), or its equivalent in Saum (fasting), that he may taste the heaviness (punishment) of his deed. Allâh has forgiven what is past, but whosoever commits it again, Allâh will take retribution from him. And Allâh is All-Mighty, All-Able of Retribution. Sura Al-Ma'ida:59 (5:59)
When they entered in upon Dâwûd (David), he was terrified of them. They said: "Fear not! (We are) two litigants, one of whom has wronged the other, therefore judge between us with truth, and treat us not with injustice, and guide us to the Right Way. Sura Sad:22 (38:22)
O Dâwûd (David)! Verily! We have placed you as a successor on the earth; so judge you between men in truth (and justice) and follow not your desire - for it will mislead you from the Path of Allâh. Verily, those who wander astray from the Path of Allâh (shall) have a severe torment, because they forgot the Day of Reckoning. Sura Sad (38:26)