Key legal question
Whether ordering a full fitness-to-drive examination was proportionate after a positive cocaine hair test with possible external contamination.
Extracted holding
A further control examination with hair analysis was sufficient at this stage; a full fitness-to-drive examination was premature.
Extracted reasoning
The positive cocaine finding was not beyond doubt proof of consumption because external contamination could not be excluded. Given the proportionality principle, the less intrusive hair-based abstinence control was the appropriate first step.