For once, it was the Intoxilyzer 5000 being "tested." And the results weren't so favorable to the machine's manufacturer, CMI, Inc.of Owensboro, Ky.
The Kentucky Court of Appeals ruled CMI Inc. must reveal its source code or computer software program. The Intoxilyzer 5000 is the same breath machine used for sobriety testing in Virginia.
The ruling stems from a case in the lower courts where Lennie House was arrested in Kentucky under the presumption of driving under the influence. A breath test via the Intoxilyzer 5000 given to House showed his BAC at 0.18.
Four months later, House filed a motion that the Commonwealth of Kentucky must force CMI Inc. to reveal its source code. When the Commonwealth failed to secure the source code, House subpoenaed CMI. In response, both the Commonwealth and CMI filed motions to quash House’s subpoena. House then filed a subpoena to drop the Intoxilyzer 5000 results based on the two parties’ failure to comply.
What If There Are Bugs in the Source Code?
A subsequent hearing was held where House produced a computer software engineer, who testified that if the source code were revealed, he could examine it to look for computer “bugs” or flaws in source code logic, which if found would render the BAC reading erroneous.
In September, Fayette County District Court ruled that both parties had a right to quash House’s subpoena. House then entered a guilty plea but held the right to appeal the district court’s ruling. In January, the Fayette County Circuit Court affirmed the District Court’s ruling.
Before the Commonwealth of Kentucky Court of Appeals in January 2008, House said the district court erred in granting the two parties’ motions to quash his subpoena seeking the computer source code. The Court of Appeals sided with House, determining his request was reasonable since it challenged the validity of the machine’s findings. Thus, the ruling by the Fayette County Circuit Court was reversed.