U.S. Capitol Building

Confronting the Silent Witness — the Breath Test Machine — in a DWI Case

Jamison KoehlerDUI and Driving Offenses


The government vouches for him.  He himself doesn’t need to come to court, much less explain the basis for his conclusions.  His “testimony,” which is delivered through an interpreter, consists of nothing more than a couple of numbers and some pre-set generic language. There is no opportunity to cross-examine him. And yet the court can send the defendant away for months, even years, on the basis of his testimony alone.

The witness is not a person but a piece of equipment; it is the breath test machine used in a per se DWI case.

The Sixth Amendment guarantees a person who has been accused of a crime the right “to be confronted with the witnesses against him.”  The U.S. Supreme Court held in Crawford v. Washington that, in cases in which the accuser is not available for trial, the  accuser’s “testimonial statement” against the defendant can only be used if the government can satisfy two conditions.  First, the government must prove that the accuser is unavailable for trial.  Second, the government must prove that the defendant had a prior opportunity to cross-examine the accuser.

In Melendez-Diaz v. Massachusetts, the Supreme Court refused to find a “forensic evidence exception” to the rule in Crawford.  More recently, in Bullcoming v. New Mexico, the Court held that the government cannot meet its obligations under the 6th Amendment’s Confrontation Clause by introducing “surrogate testimony.”  Specifically, it held that the government cannot substitute the testimony of a lab technician who was familiar with the procedures used in analyzing a blood sample for the presence of alcohol for the testimony of the technician who had actually conducted the test.

The government will undoubtedly argue that there is nothing in these Supreme Court decisions that prohibits continued use of a breath test instrument – for example, the Intox EC-IR II that is used in D.C., Virginia and many other jurisdictions — to secure a conviction for a per se DWI offense.  The government will acknowledge that the breath test ticket that displays the subject’s blood alcohol level at the time of testing is clearly a piece of testimonial evidence that falls within the scope of the Confrontation Clause.  At the same time, the government will argue that, assuming that the defendant has availed himself of the “notice-and-demand” procedures used in many jurisdictions to assure that the breath test operator is present at trial, the defendant will have ample opportunity to cross-examine the government’s key witness against him.   For example:  Did the operator observe the defendant for the required time period in advance of the test to assure that the defendant did not hiccup, belch or burp, thereby introducing alcohol back into the mouth and contaminating the result?  Was the subject adequately advised of the procedures for taking the test?  And so on.

The breath test operator’s testimony at trial would satisfy the Melendez-Diaz requirement of a “live witness” in order to introduce a forensic laboratory report.  And Bullcoming required only that the analyst who actually conducted the test be present at trial to testify to the results of that test.

The problem with this argument is as follows:  The police officer who operates a breath test machine in a DWI case is completely unlike the laboratory technician in Bullcoming. The technician in Bullcoming undertook a fairly complicated scientific and technical procedure to determine the level of alcohol in the subject’s blood.  As the Court noted in that case, use of the gas chromatography machines employed in Bullcoming “requires specialized knowledge and training”:  “In order to perform quantitative analyses satisfactorily and . . . support the results under rigorous examination in court, the analyst must be aware of, and adhere to, good analytical practices and understand what is being done and why.” (Emphasis added.)

This is not the case with the operator of a breath test machine. First, unlike the laboratory technician in Bullcoming who presumably had at least a college degree in science or technology, the operator of a breath test machine is typically a police officer who received at best a couple of hours of training in the operation of the machine.  Having been trained in the operation of the machine myself, I can tell you I knew enough about the machine to testify knowledgeably in a court of law after the first half-hour of training.  You replace the mouthpiece, you type in some information, you instruct the subject on blowing, and then you push a few more buttons before the machine spits out a result.  A 10-year-old could be taught to administer the machine assuming s/he knew how to type.

But neither I, nor the police officer, nor the 10-year-old child would have any idea how the machine came to its result. Nor would, in the words of Melendez-Diaz, someone with the “scientific acumen of Mme. Curie and the veracity of Mother Teresa.”  And that’s because the source code to the equipment– the software that determines the machine’s calculations — is the proprietary information owned and protected by Intoximeters, Inc. of St. Louis, Missouri, an out-of-state company completely immune at least in Virginia from subpoena power.  As a prosecutor in Alexandria recently crowed to me, not even the government has access to that information.  I can only assume that, with all the government’s ability to protect business confidential information, the government wants it that way.

Having provided this context, I will now repeat the allegations I made in the opening paragraph.

The government vouches for him.  In Virginia, for example, the EC-IR II is one of two machines approved for DWI testing by the Department of Forensic Sciences.  In how many other situations is a party allowed to vouch for a witness’ veracity before he has even testified?

He himself doesn’t need to come to court, much less explain the basis for his conclusions.  His “testimony,” which is delivered through an interpreter, consists of nothing more than a couple of numbers and some pre-set generic language. The police officer who dutifully punches in the numbers and produces the breath test ticket has no understanding – and no ability to understand – how the machine arrives at its conclusion.  As such, apart from a few observations on the correct administration of the test, he offers nothing more to the court’s understanding of the issues involved than would an interpreter who was translating into English the words of a non-English-speaking witness.  He is, in Bullcoming’s words, a “mere scrivener” and the breath test ticket nothing more than “raw, machine-produced data.”

There is no opportunity to cross-examine him. The real witness in this case, if not the machine itself, would be someone with an understanding of the source code; in the case of EC-IR II, someone from Intoximeters, Inc., in St. Louis.  This is the only person who could, in the language cited by Bullcoming, “understand what is being done and why” and stand accountable to the defense.  And yet this person, in Virginia anyway, is completely immune from subpoena.  (How this impacts a defendant’s constitutional right to “compulsory process” will have to be dealt with separately.)

And yet the court can send the defendant away for months, even years, on the basis of his testimony alone. In order to secure a conviction for a per se DWI offense, the government need prove only that:  (1) the defendant operated or was in physical control of the car, and (2) the defendant’s blood alcohol content at the time of driving/test was 0.08 grams or more per 210 liters of breath.  (This is opposed to driving under the influence (DUI) in which the government is generally required to prove some type of impaired driving as a result of intoxication.)

Depending on the blood alcohol level and the defendant’s prior criminal history, a person convicted of per se DWI can be sent to prison for years.  The penalty for a third DWI conviction within 10 years in Virginia, for example, is a term of imprisonment of one to 5 years and a maximum fine of $2,500, with a mandatory minimum sentence of 90 days.

The accuracy of breath tests machines used throughout the country is a great fiction perpetrated by state legislatures in order to maintain the viability of programs to eliminate drunk driving.  While I fully support this objective, no end is worth the wholesale degradation of our constitutional rights; in this case, the denial of a defendant’s right to confrontation. As the Supreme Court held in United States v. Gonzalez-Lopez, “the purpose of the rights set forth in [the Sixth] Amendment is to ensure a fair trial; but it does not follow that the rights can be disregarded so long as the trial is, on the whole fair.”  If a “particular guarantee” of the Sixth Amendment is violated, no substitute procedure can cure the violation, and “[n]o additional showing of prejudice is required to make the violation complete.”

This is what is happening with the breath test machines.  Courts maintain the fiction that, because the defendant is in fact given the opportunity to cross-examine the police officer who operated the machine, this is close enough to true confrontation.

At a DWI conference in Williamsburg, Virginia, a couple of months ago, one of the nation’s leading experts on breath test technologies claimed that alternative and more transparent technologies are in fact already available; we just need the willpower and resources to develop them.  With the impetus behind anti-drunk driving programs, you can believe that, were courts to start throwing out cases on the basis of the constitutional violations described above, these alternative technologies would quickly find their way to market.