How to read a result

On your device, the lab checks for identical files and looks for a block of writing or an isolated mark in each image. If the region is unclear, take a closer photograph and keep the full-page image too. The overlay shows where outlines meet and diverge, but cannot identify the signer or authenticate the document.

Forensic methods

Image overlays

Superimposing two regions helps locate agreement and disagreement between outlines.

Forensic methods

Referring an original to an examiner

A focused question helps determine which materials to submit and how to plan the examination.

Worked examples

Writing a finding in a preliminary report

Make the observation, alternative explanations and missing material clear.

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