In much (most? all?) of the United States, life insurance contracts generally cover suicide, except that individual policies will typically have 2-3 year exclusion period.

My individual term life policy has a 2-year exclusion period, but otherwise covers suicide. I can't track down the precise reasons for this, whether its related to case law, state statutes, etc. Closest hit I found for California was Insurance Code § 11066(h), but that's for policies issued by fraternal societies. (It probably echoes some other statute or case law.) There are endless Google hits from law and insurance web sites stating this general fact.

Do you have sources for this? Here in El Salvador we have highways without lamps, streets that drivers treat as highways, crosswalk where you cannot longer see the painting.

I guess you're referring to the U.S., right?

That's completely false. Among many other factors, about 50% of single-car crashes involve passengers, which would imply a disturbingly high number of murder-suicides.

are you counting unintentional like falling asleep behind the wheel?