Model the attack, not only the identity check
Fraud can use stolen real identities, fabricated evidence, synthetic combinations, coerced users, compromised devices or genuine accounts controlled after onboarding. Controls should follow the customer lifecycle from application through recovery and high-risk actions.
Document attacker objectives, available evidence, automation capability and expected adaptation. A control that works in a laboratory may degrade when exposed to retries, routing and adversarial feedback.
Combine independent evidence
Understand signal provenance, latency, geographic coverage and failure behaviour. Correlated signals should not be counted as independent proof.
Orchestrate proportionate outcomes
Use policy to decide when to approve, reject, request more evidence or send a case to review. Preserve the reason for each outcome and prevent attackers from learning exact thresholds through detailed error messages.
- Limit retries and detect evidence reuse
- Apply step-up checks to risky sessions or actions
- Separate uncertain cases from confirmed fraud
- Give reviewers relevant evidence without overwhelming them
- Feed confirmed outcomes back into measurement and controls
Measure protection and customer harm together
Track detection, loss and confirmed fraud alongside false rejection, abandonment, manual review and support contacts. Segment metrics to uncover weak markets, devices or journey paths.
Before changing decisions, compare the new signal or policy with existing outcomes and investigate disagreement cases.
Ask how models are validated, monitored and changed; which explanations are available; and how your organisation can override, audit and export decisions.
