Video Spectral Comparison

A questioned medical record that appears to have been written with one pen.  The third line under the “11/16 – 3:30P” entry is specifically in question.

Foster & Freeman's VSC-4

The questioned area (“Pt advised possible ataxic gait”) in the VSC before infrared filtering.

The questioned area view at a infrared wavelength of 795nm.  The suspect writing “disappears” proving that a subsequent entry was made to the record using a second pen.  The ink in the first pen reflects light in the infrared end of the spectrum, the second pen does not, seemingly disappearing.  This same method works exceptionally well in obliteration cases when the obliterating (overwriting) ink also vanishes, making the underwriting easily read.

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