In the 153 postmortem cases in which methanol was detected, the presence of formate concentrations greater than 0.5 g/l in blood or vitreous humor strongly indicated that the methanol was ingested during life and the methanol and formate were at least potentially life-threatening. This leads to the conclusion that the methanol was not present as an artifact or an accident of specimen collection. On the other hand, the following conditions were indicative that the methanol had been introduced into one or more parts of the body as an artifact rather than through ingestion during life: finding methanol in the absence of formate; formate concentrations substantially less than 0.5 g/l in the blood or vitreous humor; or the presence of methanol at markedly different concentrations in blood compared with vitreous humor or vice versa. From all death cases investigated by a medical examiner in Alberta (Canada) between 1986 and 2005, all cases in which methanol was detected were included, with the following exceptions: where the body was embalmed, when the postmortem blood or vitreous methanol concentration was less than 0.2 g/l, or when death was delayed due to the effects of methanol poisoning and a hospital-admission blood sample was unavailable. An automated headspace gas chromatography method was developed for the determination of formate in postmortem specimens, based on the in situ sulfuric acid-methanol methylation of formic acid to methyl formate. Diisopropyl ether was used as an internal standard. 3 tables, 5 figures, and 24 references