Is the financial fine imposed by the unjust court, as a result of my hitting a young man who assaulted my sister, considered a debt that I must pay, or am I not obliged to pay it because I am wronged?

A Muslim must enjoin good and forbid evil, and their changing of evil should not lead to a greater evil. They are not permitted to strike others. Whoever does not feel protective jealousy over their female relatives is considered a dayyūth (one who lacks protective jealousy). If an assault occurs, Islamic law dictates qisas (retaliation in kind) or arsh al-jinaya (compensation for injury) if forgiveness or reconciliation is not reached. If the crime is proven and the secular court issues a ruling, that ruling becomes binding if it conforms to Islamic law or does not contradict it.