From my anecdotal evidence, corroborated by many TV threads, farang in Thailand are disastrous drivers.
First, they drive on the wrong side of the road (if they are Americans or Europeans).
Second, most don't have a license, ie they don't have the license to drive the kind of vehicle they drive here. People who have never in their life operated a motorcycle do it here all of the time. In their home country, they wouldn't dare to do it without the proper license. Here, I have been asked whether one needs a license at all to drive.
And they can't read Thai traffic signs.
Then, farang in Thailand are usually old, slow, poor vision, sleepy reflexes, but stubborn. Many wouldn't be considered roadworthy in their home-country. And they are usually drunk.
Finally, most farangs know that they are superior beings. They cannot even imagine that their driving is less than perfect. And they are always quick to blame "the Thais".
From this not-so-scientific analysis clearly follows, aliens should be relegated to walking.