John Mazor writes:

Then they must get a lot of cases that go to court because that's bad science.

They get a lot of cases because some people still cannot prevent themselves
from drinking and driving. Those people often go to jail. There's nothing
wrong with the science.

You can get a non-zero reading without consuming alcohol, even with
lab-grade equipment.

All you have to do is prove that it's not alcohol.

That's why the FAA allows up to a .02% BAC reading before flying.

It should be zero.