Once a plaintiff lodged a complaint before Umar ibn al-Khattab, the Caliph of those days. Both parties of litigation should appear before the court and lay their complaints.
The one against whom the complaint was lodged was Imam `Ali (a.s). Convoking both parties, Umar went and sat down on the seat of judgment. According to the Islamic law, both parties ought to station next to each other and the principle of equality before the Tribunal should be respected.
Accordingly, the Caliph called out the plaintiff by name and beckoned him to stand up in a peculiar place before the judge. Then he turned to `Ali and said, “O Abu’l-Hasan! Place yourself next to your plaintiff.”
On hearing these words, `Ali became apparently angry.” The caliph said, “O `Ali, you do not want to stand next to your adversary.”
`Ali said, “No, that is not the reason for my anger; the reason is that you have not entirely respected the norms of justice, for you called me respectfully by my nickname Abu’l-Hasan but you called the other person by his ordinary name.”
Umar hugged the Imam and kissed him between the eyes saying, “May my father be your ransom! Allah guided us with your mediation and brought us out of darkness into light through you.”
Sharh Nahj al-Balaghah: 65/17.
Fu¤ayl ibn al-Ja`d reports: The main reason the Arabs did not support Imam `Ali was the wealth. He never preferred an Arab to a non-Arab or an aristocrat to an ordinary man. He never compromised with the chiefs of tribes nor with the kings. That is why the people abandoned `Ali and joined Mu`awiyah. `Ali complained to Malik Ashtar of his companions, failure to support him and the escape of some of them to Mu`awiyah. Malik Ashtar too would say, “O Amir al-Mu’minin! Some people cannot tolerate your justice, for they are the people of the world! May Allah pave the way for your justice, oppress your enemies, disperse them, foil their plan and break their unity against you: Surely He is Aware of what they do.”
In response, `Ali said, “As for our just acts, Allah says:
مَنْ عَمِلَ صَالِحًا فَلِنَفْسِهِ وَمَنْ أَسَاءَ فَعَلَيْهَا وَمَا رَبُّكَ بِظَلَّامٍ لِّلْعَبِيدِ (46)
Whoever does good, it is for his own soul, and whoever does evil, it is against it; and your Lord is not in the least unjust to the servants. (41: 46)
As for your opinion that justice is hard for them hence they abandoned us, Allah knows that they did not leave us for any injustice. They left us for worldly riches, a world which they will leave and on the Judgment Day. They will be questioned whether they fought for the world or Allah! As for saying that we do not give away to them from the public fund, we cannot give them more than what they deserve. Allah says:
كَم مِّن فِئَةٍ قَلِيلَةٍ غَلَبَتْ فِئَةً كَثِيرَةً بِإِذْنِ اللّهِ وَاللّهُ مَعَ الصَّابِرِينَ (249)
How often has a small party vanquished numerous hosts by Allah’s permission, and Allah is with the patient. (2:249).
Allah commissioned Muhammad as a prophet with a small number of people around him but they increased in number and honored them while they were humiliated before. If Allah wills, He will support us, remove our problems and sorrows. I approve of your union which pleases Allah. You are the most benevolent and trustworthy of them with me, Allah willing.”
Ref: Al-Gharat: 46/1.