We reported in May that LGC Forensics had erroneously reported DNA profiling results in two different cases (LINK). This latest mix up relates to drugs, discovered only when our expert, Richard Brown, was instructed to re-analyse several exhibits, one of which the defendant denied contained any illegal substance. Our testing showed that the sample contained citric acid, not mephedrone as reported by the LGC scientist. On investigation, it appeared that the same vial, containing a small sample of one of the drug exhibits, had been tested twice and the citric acid exhibit had not been tested at all. LGC eventually admitted their mistake and the case was dropped. This case emphasises the need to look carefully at the continuity of exhibits, not just to focus on interpretation of the final results.