«إِنَّهُ جَدَلَهُ خَاسِيًا وَأَفَاحَ دَمَهُ خَالِيًا، فَأَنَّى لِي شَاهِدٌ وَلَمْ يَكُنْ ثَمَّ مُشَاهِدٌ»
He struck my son down in disgrace and shed his blood in solitude; how could I have a witness when no one saw it?
Fa-annā lī shāhid is a rhetorical question: how could I produce a witness? wa-lam yakun thamma mushāhid gives the speaker’s reason—no spectator was present. The matching root of witness and spectator concentrates attention on evidence.
It establishes that the litigant offered this explanation. It does not independently prove a homicide or the other party’s innocence. Subsequent revelation changes how the claim should be evaluated.
Differentiate “the litigant says no witness was present” from “a killing has been proved.”