Chemical test (second step)
Posted on:1/9/2006
| If arrested, the driver is brought to the police station, and given one or more chemical tests: breath, urine, and/or blood. Breath test results are usually available immediately and are sometimes given before the actual arrest takes place; urine and blood samples are sent to a lab to determine the BAC. |
In some jurisdictions, refusing to take a breathalyzer test is an offense in itself, often creating an automatic presumption of guilt under the law.
If a person is involved in a motor vehicle accident involving a fatality or serious physical injury, and is suspected to be intoxicated, some jurisdictions permit the police to forcibly take a sample of the driver's blood without their consent. This is usually only done after a warrant is obtained from a judge.
While chemical tests are used to determine the driver's BAC, they are unable to determine the driver's level of impairment. In addition, their accuracy is disputed by some (see blood alcohol test assumptions). In any case, tests can only determine the BAC at the time the test is taken, which can be higher or lower than when the vehicle was actually operated. Since it would be impossible to obtain a chemical test while the driver is actually operating the motor vehicle, chemical tests are the primary means used to prove intoxication or impairment.