In many instances, an Illinois driving under the influence, or DUI is won or lost based upon the trier of fact (the judge or jury) receiving the results of a breath test. By way of background, there are two types of breath tests that a driver suspected of driving under the influence (DUI) will face.
At the roadside, the police will first administer a series of standardized field sobriety tests. These are physical tests that purportedly correlate with a blood alcohol content (BAC) of at least .08.
A BAC of .08 is the minimum level at which the law assumes you are under the influence of alcohol. 625 ILCS 5/11-501.2 This figure represents how much alcohol has entered your bloodstream, the point at which alcohol negatively effects those parts of the brain that regulate skills related to driving, such as vision, judgment and reaction time.
Furthermore, at the roadside, the officer will also ask you to blow into a handheld device. This is known as a preliminary breath test (PBT). The results of this test are not evidence of your BAC but are merely a tool to help the police determine whether to arrest you for DUI. 625 ILCS 5/11-501.5
Following the arrest for DUI, the police will ask you to submit to a chemical test to determine your BAC. The chemical test is the “official” test, as the results of it are admissible to prove your BAC, Unlike the field sobriety tests, the chemical tests are considered direct evidence of your blood alcohol content.
The chemical test is usually administered at the police station, although there are certain testing machines that are certified for use in the field. Unlike the PBT devices, these machines, as well as any machines that produce “official” results, are subject to certain certification requirements. Likewise, the operator of the machines must be certified and the method of administering the tests is also regulated by law. 625 ILCS 5/11-501.2
As far as the manner in which the test must be administered, the law requires that the state follow procedures set forth by regulations that the Illinois State Police promulgate. These rules are found at 20 Illinois Administrative Code Part 1286. Failure to comply with these regulations makes the results of the test inadmissible in court. People v. Emrich, 113 Ill. 2d 343, 498 N.E.2d 1140, 101 Ill. Dec. 632 (1986)
Furthermore, in order to introduce the results of the test, the State must show that the operator of the device was properly certified by the Illinois State Police, that the machine was approved, that it was tested regularly for accuracy and that it was working properly. The prosecution must additionally present evidence that the motorist was observed for 20 minutes before being tested. Finally, the State must show that the results on the tape printed out and presented in court are those of the defendant.
Another issues that arises in breath test admissibility stems from the Confrontation Clause of the United States Constitution. In any criminal prosecution, the accused is, under that Clause, entitled to confront his accuser. Bullcoming v. New Mexico, 131 S. Ct. 2705, 180 L. Ed. 2d 610, 79 USLW 4618, 11 Cal. Daily Op. Serv. 7706, 2011 Daily Journal D.A.R. 9225, 22 Fla. L. Weekly Fed. S 1213, 2011 WL 2472799 (2011) In essence, this case held that the prosecution must bring to court each witness who performed any of the testing, analysis, collection, or certification that is pertinent to the test.
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What blood tests can be used against me in an Illinois DUI prosecution? September 28, 2012, Illinois DUI Lawyer Blawg