“No, I say you treat stoned drivers just as you would treat drunk ones: lock ‘em up and pull their ticket.”
Yeah...got a field sobriety test for that? Silly? Why...you are the one advocating “saving big money” by feeding the tax coffers and eliminating certain policing functions...good luck with dismissing that with don’t be silly...isn’t that what the Greeks said?
They pop people for it every day so I reckon they do. But absent that there is a violation in most places for failure to maintain reasonable control of a vehicle. That is a solid principle that doesn't need to distinguish why someone is driving unsafely (drunk, stoned, texting, falling asleep - unsafe is unsafe). If "safety" is what you want that ought to work just fine. No need to make people do parlor tricks or for the taxpayers to spend time & money on chemical tests. The government police just does it's job - observes unsafe driving, cites for it, and proves it in court.