How Do You Choose a Source of Truth When Business Systems Disagree?

Start with the decision the source must support

There is rarely one source that is authoritative for every field. A billing system may be the source for payment status, a scheduling system may be the source for appointment time, and a signed form may be the source for an approved contact detail. Before cleaning a record, define which decision each source is allowed to support.

Write the field, source, time boundary, owner and acceptable evidence in plain language. "Use the CRM" is often too broad. "Use the payment processor for settled status as of the transaction timestamp" is a testable rule. If two sources are authoritative for different moments, preserve both rather than overwriting one with the other.

Do not resolve a conflict by choosing the tidier value

When systems disagree, compare identifiers, timestamps, definitions and update paths. A more complete-looking field is not necessarily more reliable. Mark the conflict, retain the original values, and state the smallest next check that could settle it. If the available evidence cannot settle it, use an explicit unknown state.

For customer-facing, financial, employment, health or legal workflows, route the decision to the person responsible for the policy. A cleanup tool can organize the evidence and proposed choices; it should not silently decide which source wins.

Keep the rule reviewable

Record why a source was selected, which fields it covers, when the rule applies, and how to reverse a change. Revisit the rule when a system changes its field definition or when the business process changes. The source-of-truth checklist is part of the workflow, not a one-time note.

AI Cleanup Doctor can help structure a redacted conflict review with source definitions, evidence and next actions. It does not certify a source, replace ownership or make a business decision.