Professor Vinci Luminol Print Analysis

Murder of Meredith Kercher
Court of Perugia
Prof. Francesco Vinci
Professor of Forensic Medicine and Forensic Pathology
(pages 42-65 the original Italian)

Positive luminol print (#2 of 18 Dec 2007).

Preliminary considerations. There are significant elements attributable to “sliding” and not simply a perpendicular contact.

The photographs taken in the dark in order to document the traces highlighted by luminol are necessarily always taken under extreme conditions and in any case the relationship between very long exposure times and choice of aperture are critical. The resulting images can therefore be very suggestive, but certainly do not correspond to the effective reality or to that visible to the naked eye.

Red lines = reference lines. Print revealed by luminol. Analysis of the shape of the sole by making both the same size on the basis of the distance between the apex of the big toe and the heel.

The print of the second toe is very evident, which we have already demonstrated is absence in Sollecito’s right foot, as demonstrated in the baropodometric test. The print of the first phalange of the big toe is also very evident.

Mapping of the line obtained by connecting the apexes of the toes of Sollecito’s right foot. Note the apex of the second toe.

Mapping of luminol print and Sollecito’s foot are entirely different when noting the apex of the second toe.

Morphological analysis of the luminol print and Sollecito’s foot using true measurements. Missing placement of second toe. Different position of all the toes. Different placement highlighted for the phalangeal metatarsal of the second toe.

Even in this instance, the negative result of the morphological comparison negates the need to continue to the second phase of the investigation. Therefore once again we must exclude that the print in question can be in the slightest way attributable to Raffaele Sollecito.

Second phase of investigation. Metric analysis. All our measurements were taken utilizing a professional computer program for dimensional morphometry, Image-Pro Plus (Media Cybernetics, Silver Spring, MD, USA)

Method adopted by the Scientific Police in choosing the units of measurement (Rinaldi-Boemia). “Utilizing the photographic images in conditions of correct lighting (print #5) we proceeded in the linear measurement of the width of a tile. The measurement of this tile (corresponding to the area in which two prints were revealed) permitted us to identify a width equal to 169.3 mm. This measurement was brought to print #2 corresponding to exactly the same segment measured under illuminated conditions (visible also in the image taken in the dark), allowing us to resize the image and permitting the subsequent measurements.”

The camera should be fixed on a tripod so that the lens is perpendicular to the print, so that the relative distances are not altered.

From Rinaldi-Boemia’s analysis or the print #2 of 18 Dec 2007, size of the shorter side of the tile indicated as 169.3 mm by the Scientific Police.

About the resizing of Rinaldi-Boemia’s analysis. “Once the second luminol-positive print was resized it was measured.

Our measurements. The size of the tiles which are used in flooring (in all environments) are 337.76142 x 163.80602 mm in our measurements. In particular, the measurement of 163.80602 that we measured differs significantly from that measured by the Scientific Police (169.3), who define this measurement as the width.

During the hearing, Dr. Rinaldi admitted that there was a discrepancy between the measurements taken of the tiles, stating that the reason was due to the effect of parallax which he tried to overcome by deforming the images. The measurements obtained with this method are closer to those that we found, however the measurements taken and shown by the Scientific Police are always based on the original (erroneous) parameters. Dr. Rinaldi declared that he took this difference into account, however without explaining which criteria or mathematical calculation was used.

Our calculation of the measurements.

There is a disagreement between our measurements and those of the Scientific Police in nearly all cases.

Calculation of the length of the shoe from the measurements of the foot. European system: shoe size = (length of shoe in cm x 3 / 2) + 3. In the specific case: (21.5 x 3 / 2) + 3 = 35.25. Allowing for 1cm of tolerance (the space between foot and the shoe) it must be concluded that the size corresponds to a 36 or 37. Therefore it’s a small foot, probably female.

Comparison of the print collected and Sollecito’s when correctly proportioned. Sollecito’s foot is longer by more than 3 cm!!!

Method of “color substitution” to better highlight the characteristics of the print. The prints left by the toes are more visible.

Application of the grid system as suggested by Robbins. The red spots indicate obvious points of difference.

Conclusions: Neither of the two prints collected can be considered as even being “compatible” with Raffaele Sollecito, rather it should be certainly excluded that these prints were left by him.

In any case: It is always preferable to use the term “non attributable” to the general concept of “compatibility” or, worse, to “probable identity” which, having too many limitations and not being defined on a solid scientific basis, can be utilized erroneously.