Drive Awake · Perspectives · Law
A trial without measurable evidence. Ten years on, the question raised by the Quinto case is still open: how do you prove a danger that leaves no trace?
Analysis| 26.09.2026 | Quinto case, legal reference and IRM study clarified |
Ten years ago, on 26 July, on the A2 motorway near Quinto, a vehicle ran into a car stopped in a queue. The medical expert report found that the driver had severe obstructive sleep apnoea, which he was unaware of and which was diagnosed only afterwards. No alcohol, no deliberate distraction. The proceedings ended in an acquittal, which does not establish any wider conclusion about the facts. The facts are gathered in the Quinto case; here we follow only the question it left open.
The law rests on proof. For alcohol there is a value in the blood; for speed, a recorded figure; for distraction, often a phone log. Not for sleepiness. It leaves no residue in the body, appears in no record, cannot be measured at the scene. By the time a crash has happened, the proof that the driver was sleepy almost always no longer exists. Clues remain - no braking, the hour, the dynamics - but not a measure.
Swiss road traffic law places responsibility before the journey: whoever is not fit to drive, including because of sleepiness, must not drive (art. 31 para. 2 SVG/LCStr and art. 2 para. 1 VRV/ONC). It is a rule of prevention. But the trial looks backward, trying to establish what the driver knew or should have known. With an undiagnosed condition - a silent apnoea - even that line becomes uncertain.
Research is now starting to look for a trace. A study by the IRM in Zurich identified, in the laboratory and in a group of 20 men, markers in saliva linked to acute sleep deprivation (DOI 10.1021/acs.jproteome.5c01064): a proof of principle, not yet a roadside tool. It does not change the Quinto case. But it points a direction: what left no trace is beginning, perhaps, to leave one.
The open question
A test is not there to punish afterwards. It is there to help stop beforehand. If one day sleepiness has a measure, it will not be to find someone to blame once the crash has happened, but to recognise the risk while there is still a choice to make. Prevention, not prosecution: that is what the limit of proof is about.
Quinto case: crash on the A2, sleep apnoea diagnosed after the crash. Anniversary 26 July.
Swiss Road Traffic Act (SVG/LCStr, RS 741.01), art. 31.
IRM Zurich saliva study, DOI 10.1021/acs.jproteome.5c01064.
Registered field study (NCT07089342, completed in December 2025 according to the registry; results not yet published).
Stay awake, at the wheel and in life.