What is the margin of error for chemical DUI tests?

What is the margin of error for chemical DUI tests?

Neil Shouse (Defense Attorney) gives expert video advice on: What are 'chemical tests' as they are used in a DUI arrest?; What is the 'implied consent law'?; When does a motorist have the right to refuse a chemical test during a DUI arrest? and more...

The margin of error on a blood test is thought to be .005, so if a blood test comes back let's say .08 that would presumably mean that range of true Blood Alcohol Content would be between .075 and .085. The margin of error is higher on breath tests, but it's generally thought to be between one and two percent. We take the 2% benchmark if somebody blows into the breath test machine and the reading is .08 that would mean the true BAC is somewhere between .06 and .10