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Effects of RFI (Radio Frequency Interference) on Breathalyzers How States Are Handling Court Challenges

NCJ Number
93990
Journal
Court Review Volume: 21 Issue: 2 Dated: (Spring 1984) Pages: 18-23
Author(s)
D Farthing-Capowich
Date Published
1984
Length
6 pages
Annotation
The problem of radio frequency interference (RFI) with certain breathalyzer models has been resolved either on a case-by-case basis with reliance on expert testimony or on a statewide basis relying on a combination of court rulings and adherence to RFI testing protocol.
Abstract
In January and September of 1982, Smith and Wesson distributed advisories to its customers regarding the potential for inaccurate test results from their 1000, 900, and 900A models because of radio frequency interference. The guidelines for testing the units to detect whether RFI affects the machines' reliability were included in the advisory. The National Bureau of Standards tested the models and found that the 900 model is generally not susceptible to RFI, and although the 900A's are more susceptible, very few of the units were actually affected when used. Under certain circumstances, prior drunk driving convictions based on test results of the Model 900A can be reopened and set aside on the theory of newly discovered evidence. To obtain more detailed information from the States using Smith and Wesson Models 900 and 900A, the National Center's Research and Information Service conducted a telephone survey from September 19 to October 5, 1983. The survey results revealed that most States have experienced relatively limited problems because of RFI effects on breathalyzers. Virtually all States reported that defense attorneys had raised RFI as an issue during pretrial motions or at trial, but with little success. Generally, the key to defeating such challenges has been presentation of evidence concerning RFI testing results for individual machines and adherence to operational standards and procedures. One figure and 19 notes are listed.