Breath testing in DUI cases relies on the presumption that every subject has a "normal" body temperature. But what if a subject has a fever? One study (Fox & Hayward, 1989) did reveal problems with DUI breath tests for those with higher than normal body temperature levels. For example, when the core temp was elevated one degree Celsius, the corresponding breath test for alcohol increased by nearly 9 percent. This means that if a person had an elevated body temp and was stopped for drunk driving, his breath test would falsely inflate his true blood alcohol level by almost 10%. For a .10 level, this would drop him to a .09 and if he blew a .08, his true BAC would actually be .07.
For more information on this issue, contact DUI Attorney Matthew Ruff who practices in the state of California.