For the purpose of assessing possible opiate dependence (question of culpability) toxicological tests (gas chromatography; mass-spectrometry) were performed on cuttings of hair of a 30-year-old man who had within a short period committed several punishable offences 8 months previously. It was thus possible to determine opiate intake over a period of time corresponding to the length of hair. About 20 micrograms/g codeine and up to 4 micrograms/g morphine were demonstrated, in addition also 30 micrograms/g bromazepam. These results proved that amounts exceeding therapeutic levels of bromazepam and codeine-containing drugs had been taken during the period in question.