Leskie Database False Match

This case involved the Victoria Police Forensic Services Centre (Australia). DNA evidence from a murdered child was erroneously matched to a DNA profile in a database of convicted felons and victims. After a lengthly hearing the Cororner concluded, as did most experts, that a contamination event in the laboratory lead to the false match. Interestingly, the lab argued that this 10 locus match was a coincidental match or as Bruce Weir suggested, the evidence may have come from a relative of the person in the database.

An interesting aspect of this hearing was the implicit discussion about what might be more rare a coincidental 10 locus match or a lab error. All the experts in this case acknowledge never seeing a match at more than 9-loci between unrelated individuals, nevertheless the Victoria Ploice Lab was willing to suggest that this was still more likely than a lab error. If lab errors were really as rare as a 10-locu match would the web page you are looking at have this many examples of false matches? I find that unlikely! Pages 64-85 of the Coroners report discuss the DNA evidence in this case (Coroners report).