DEFINITION
Benford's Law
Benford's Law describes the expected frequency of leading digits in many naturally occurring numeric datasets, where the digit 1 appears as the leading digit about 30% of the time and 9 about 5%. Material deviation can indicate fabricated or manipulated figures.
In forensic analytics, Benford analysis is a ranking signal rather than a conclusion. It identifies populations worth examining — manual journal entries and expense claims are the usual candidates — but a deviation has many innocent explanations, including price points, thresholds, and rounded contractual amounts.
A finding should never rest on Benford analysis alone. It is used to prioritise, after which corroborating tests establish whether the deviation reflects genuine anomaly.