A witness can be frightened into silence, or bought, or confused on cross-examination, or simply outnumbered by other witnesses telling the preferred story; a witness is a human being, with all the human vulnerabilities the powerful know exactly how to exploit.

And crucially, a witness remembers imperfectly — memory is malleable, suggestible, kind to the self, and a determined family can, over years, actually reshape what the people around them recall, until even honest witnesses misremember in the family’s favor.

But paper does not misremember.

The dated wire transfer does not soften over time out of loyalty or fear.

The signed ledger cannot be talked into a more flattering version of events at a tense holiday dinner.

The bank record has no ego to protect, no relationships to preserve, no future in the family to consider; it simply states, with perfect and pitiless indifference, that on such a date, this much money moved from here to there, and no amount of charm or intimidation or repeated retelling can make it say otherwise.