There is much confusion among defense lawyers, prosecutor's and judges as to the laws regulating the evidence in the coutroom where a defendant wishes to try a breath test to a judge or jury. In 1984, the Ohio Supreme Court issued a brutal decision that has seriously hurt the rights of the accused to challenge breath evidence at trial in a DUI / OVI case. (State v. Vega).
1. A defendant cannot ask the arresting officer any questions concerning the general reliability of the breath test machine. Evidentiary objections challenging the competency, admissibility, relevancy, authenticity and credibility of chemical tests cited in State v. French do not apply to the challenge of general reliability of breathalyzers. The Franklin County Court of Appeals held in Columbus v. Aleshire (2010) that that French "does not indicate that a challenge to the general reliability of breathalyzers is among the permissible challenges at trial".
2. Vega does not infringe on a defendant's 6th Amendment right to confront witnesses citing State v. Sabo (2004).
3. A defendant wishing to challenge any respect of a breathalyzer must lay a foundation for the witness to testify as to whatever issue is sought to be challenged. A trial court cannot allow a witness to testify about a subject on which he lacked sufficient knowledge. Columbus v. McAfee, (1991), 10th Dist. No. 90AP-944.
4. Internal diagnositc features inside the breath test machine are off limits and cannot be testified to per State v. Vega and State v. Knapke, 10th Dist. No. 08AP-933.
5. To proffer any testimony, the proponent must lay the appropriate foundation first.
6. Video tape evidence in a breath test challenge at trial has limits of admissibility. If the State dismisses the impaired charge and proceeds only on the per se charge, a defendant's good performance on field sobriety tests is not relevant to the per se offense. Accordingly, this evidence is not admissible at trial.
7. A defendant's expert toxicologist cannot testify as to the defendant's good performance on field sobriety tests in a challenge to the breath test result pursuant to Boyd and Obhof.
8. A defendant's expert toxicologist can testify concerning the amount of alcohol the defendant consumed on the night of the traffic stop to demonstrate the probability that his breath test result was incorrect. This is permissible under Day.
For a breath test challenge in the Columbus area, retain an expert, get the opinion letter of estimated BAC, and proceed to trial. It is best if the prosecution keeps the impaired charge; however, smart prosecutor's will likely dismiss that charge prior to trial. It is also likely that the defendant will have to testify and put his biometrics into evidence as well as his drinking period, food intake, and any medical issues.