N.J. Supreme Court Rules on Breathalyzer Challenges

Posted by Lawrence Taylor on March 20th, 2008

I’ve posted repeatedly in the past concerning the inaccuracy and unreliability of the various brands of breath testing machines.  (See, e.g., How Breathalyzers Work – and Why They Don’t.)  The Supreme Court of New Jersey has just turned back a challenge from defense attorneys in that state.  In New Jersey v. Chun, the Court reluctantly admitted that there were numerous sources for error in the Draeger Alcotest 7110, and directed that these be corrected by the manufacturer — but ruled that past convictions based upon the machine’s readings would nevertheless stand.

New Jersey Supreme Court Reinstates DUI Breath Test

New Jersey Supreme Court ruling brushes aside concern over the accuracy of DUI breath test machines.

New Jersey, March 19 – The Supreme Court of New Jersey on Monday reinstated the use of breath tests in convictions for driving under the influence of alcohol (DUI). The court faced a challenge to the reliability of the Draeger Alcotest 7110 breathalyzer machine from twenty defendants who combined efforts to create a sophisticated attack on the device. A total of 10,470 DUI cases had been put on hold over the course of the three-year trial — putting millions in fine revenue at risk. The court acted to uphold the convictions.

"We conclude that the Alcotest… is generally scientifically reliable, but that certain modifications are required in order to permit its results to be admissible or to allow it to be utilized to prove a per se violation of the statute," the unanimous court wrote in brushing aside the accuracy concerns.

At issue is the fact that the Alcotest machine does not directly measure the blood alcohol content (BAC) of its subject. Instead, the device estimates BAC by performing mathematical calculations on breath readings. If the calculation is not made properly, an innocent motorist can be found automatically guilty of a serious crime.

A retired judge serving as a special master spent four months pouring over arguments for and against the device’s accuracy on the high court’s behalf. The Alcotest’s maker reluctantly handed over the source code to a pair of independent software firms for analysis. The defense analysis criticized the shoddy programing and cited a buffer overflow error as evidence that the machine is not trustworthy. The court maintained that the error could be fixed with a revised firmware and that "stylistic" concerns about the software code were not relevant. The court also brushed aside concern that a "fuel cell drift" algorithm boosted the measurements by up to twenty-five percent to account for aging equipment.

"The algorithm alters the EC result in an amount that, we are confident, cannot fairly be seen as convicting the innocent," the court declared.

The court ordered a few minor changes to the firmware and error tolerance standards, clearing the way for pending cases to be resolved.

"Close enough for government work"…

(Thanks to Jonathan.)

  • michl7of9

    “putting millions in fine revenue at risk” I’ve always contended that today’s DUI laws are more about revenue than public safety. With the demonizing of he defendant there will never be social outcry for reform.

    Sad day.

  • jim


  • master zopper

    the mechine dosent work right !!! they just want the cash! we all know its a big bunch of b— s—!
    cases should be dropped and the mechine fixed , then put back out .court systems need fixed too i think

  • jim

    it’s not that it doesnt work right. my issue it that there are absolutley no regulations governing its manufacture or use in regards to method and instrument validation. none whatsoever. the point being that drager can slap these things together, sell them, and not have to prove they work in terms of real analytical validation of any kind.

  • jim

    of the 1000 points i can bring up as to instrument validsation, here is on e side note.

    how can the state prove the software loaded into the alcotest machine i was tested on uses the 2100-1 ratio?

    they can not , because there are no formal checks as to this.

    this is why in my other posts where i said the raw data for a breath test is needed in order the bac can be calculated by hand to ensure the program was using the 2100-1 ratio.

  • martifox54

    Hello from MADD National HQ –

    We are very excited to be adding an Interactive Media category to the 6th Annual MADD Media Awards. We saw your BLOG pertaining to the issues of Drunk Driving and Underage Drinking and would love to see you enter your piece in the 2008 MADD Media Awards competition. Entries from blogs must have been originally posted April 1, 2007 – March 31, 2008 qualify..

    All entries must be postmarked in the next week…before March 31 to be considered.
    MADD Media Awards
    ATTN: Tanesia Henderson

    511 E. John Carpenter Freeway
    Suite 700
    Irving, Texas 75062

    Send me an email in advance if I should be looking for a piece from you…with your name, outlet, and phone in the body of the email.

    Can I share this Media Awards entry information with someone else? Yes! If someone in your network has done an outstanding piece on these issues, please forward this email on to them.

    Marti Fox, CTC, CMP, CMM
    GlobalGoals, Inc. for MADD National Headquarters
    Suite 700
    511 E. John Carpenter Freeway
    Irving, Texas 75062

  • dwiattorney

    Interesting story. It seems the NJ SC took no concern for the accuracy of the breathalizers.

  • jim

    well, lawyers are not scientists. they were fooled into a mismash of crap, on all sides. none of the lawyers from the defense, the state, drager, or the nj supreme court got to have the basic fundamental principals of instrument and method validation explained to them nor did they get to hear about what is needed to support an analytical result.
    what i am talking about is so b asic i can not understand why none of the four defense attorneys brought it up after i made it clear to each of them what it was all about for almost a year.
    we shouldnt have to have this alcotest convict people.
    even if it just gave us the numeric value of the signal for stanards and samples so we can calculate by hand that would be a huge step in the right direction. and that is so basic and fundamental, i am speechleess at time contemplating what is going on

  • jim

    i feel so strongly i have the right to know how the alcotest works, the calculation it uses, and the raw data fro my breath test!!!!!!!
    i am beside myself!
    if the alcotest works there is no legitimate reason to hide this information from defendants.

  • scottiek

    “We saw your BLOG pertaining to the issues of Drunk Driving and Underage Drinking and would love to see you enter your piece in the 2008 MADD Media Awards competition.”

    Yeah, that would go over well. Send’em something and see what they say 🙂

    As for the article, sounds typical. I wonder what any of those judges would say if they had one drink and blew a .08.