Some time ago, whenever I was driving down the road and found myself approaching another vehicle, from either direction, I felt that my two most significant threats were that the driver might be drunk or may pick that moment to fall asleep. Neither of these had a very high probability.

Then along came the development of the SUV with a significant increase in single-car accidents, often rollovers. It seemed that there were some models that were easy to control on a straight road with no unexpected events, but if an unanticipated condition requiring a quick and often violent maneuver occurred, the driver was in serious trouble.

Even if the maneuver was successful in avoiding the problem, it often resulted in loss of control, often in a rollover.

As long as I was not driving or riding in one of these vehicles this was not of prime concern to me, but as the quantity of these vehicles increased the threat became more significant.

If their loss of control occurred as I was passing, I could become an unwilling participant.

As time went by, the manufacturers of the worst of these took steps to improve the stability, but I think that it is reasonable to require all manufacturers to demonstrate adequate stability of all models before being licensed for use on the roads of any state. This could be done by developing a test track which must be traversed in a maximum time limit, including some unscheduled events like maybe an inflated ball rolling

onto the roadway. Any manufacturer wishing to get any model qualified would have to test it at this facility.

Anyone buying a qualified vehicle that was qualified and then performed modifications would need to get it retested personally. (A supplemental type certificate in FAA lingo.)