Background The prevalence of driver suicides in Finland is about 20−30 per year. In Finland, all fatal motor vehicle accidents are investigated in-depth by multi-professional Road Accident Investigation Teams. An investigation folder is compiled from each accident and the data is also coded into a fatal accident data base. Members of the investigation teams use standardised investigation forms, which ensures the systematic acquisition of data.

Methods In this study, all the investigation folders of suicide and unclear accidents were read through to gather a more accurate data. The data gathering focused on the background factors, e.g. the preceding events, driver’s mental health problems and treatment history, medication, suicide notes, previous suicide attempts or threats, as well as the driver’s relatives opinion of the possibility of suicide. An assessment of whether the suicide was premeditated or impulsive was made.

Results During years 2008−2013 a total of 142 drivers committed suicide. Of these, 85% were male and 14% female. More than half (57%) of suicides were committed after a longer consideration and 28% were impulsive. The older the driver was, the more often suicides were premeditated. Mental health problems were common and a third of drivers (34%) were driving under the influence of alcohol (≥0.5‰). 23% of the drivers had previous suicide attempts and 36% had left a suicide note.

Conclusions The drivers who committed suicide by driving a motor vehicle had a lot of mental health problems and difficulties in life management. More than half of the suicides were committed after a longer consideration, but impulsive suicides were more common among young drivers. It was rare that the driving license issues had been taken into consideration due to mental health problems. The driver’s ability to drive, especially after suicide attempts, should be considered by health professionals and the police.