In Wikipedia there is info:
The real percentage of suicides among car accidents is not reliably known; studies by suicide researchers tell that "vehicular fatalities that are suicides vary from 1.6% to 5%".[150] Some suicides are misclassified as accidents, because suicide must be proven; "It is noteworthy that even when suicide is strongly suspected but a suicide note is not found, the case will be classified an 'accident.'"[151]
I would check the news where deaths were seen as accidents. For example don't pay electricity and use generator inside etc...