Field sobriety tests in the US are mostly a scam

I wrote earlier about how canine police units in the US are mostly a scam, and that's because not only are these drug sniffing dogs unreliable in these situations (having a considerable amount of false positives and negatives), but moreover the entire thing is extremely prone to abuse, and that's because whether the dog "alerted" is 100% based on the word of the dog's handler. If he says that the dog "alerted" then that's taken as gospel, it's the absolute fact, and there's literally zero accountability. (These incidents are never examined nor investigated for accuracy. It's the handler's word, and that's it. Zero accountability.) Rather obviously this very easily leads to abuse.

Well, there's another thing in traffic stops that's likewise prone to abuse: Field sobriety tests.

It's very similar: There are studies that show that the tests that are typically administered are unreliable, with a chance of false positives (ie. a sober person failing the tests) that's too high to be considered fair and reliable. And, like with the canine units, also here it's up to the cop's own subjective interpretation whether the driver failed the test or not. If he decides that he failed, then he failed, period: He gets arrested for "driving under the influence".

There are myriads of examples out there of completely sober people, who then pass blood test after blood test at the precinct with flying colors, who nevertheless were arrested and, quite egregiously, sometimes still charged even after all the blood tests come out negative.

And here, too, there's very little accountability. There's pretty much zero accountability if the driver gets later released without charges thanks to those blood tests (even though going to such an ordeal can be very stressful, and could potentially cause lots of other problems for the person). There's likewise very little accountability even if the driver is wrongly charged regardless of the blood tests. Even if the case is later dismissed in court, usually nothing happens to the cop who made the arrest ignoring all the evidence of sobriety.

And the thing is: A driver is legally allowed to refuse the field sobriety tests, but that's taken as an admission of guilt! 

And that's the problem: Since the result of the field sobriety test is 100% dependent on the personal subjective interpretation and word of the cop, and a refusal to take the test is taken as an admission of guilt, and because there's pretty much no accountability for the cop, this is extremely prone to abuse.

And yes, abuse happens all the time.