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Enhancing Virginia DUI defense prospects with an expert witness

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Enhancing Virginia criminal defense prospects with expert witnesses

Enhancing prospects for victory against Virginia criminal and DUI prosecutions sometimes comes in the form of turning to expert witnesses for advice and testimony.  As a Fairfax DWI lawyer, I know that the defendant’s enhancement of chances for victory is different from trying to meet or exceed the strength of prosecutors and police, because winning is about obtaining acquittal, rather than being distracted by tit-for-tat distraction. An effective criminal defense lawyer neither chases nor hides from an opponent’s power. Instead, the criminal defense warrior uses the opponent’s power and energy to the best advantage, while seeking to sense the opponent’s strategy and planned attack, to give the opponent nothing to push against, to find the opponent’s weaknesses, and to neutralize the opponent. In that spirit, when I add an expert witness to those who will testify for my criminal defense case, I remind the expert (and all witnesses) not to engage the cross examining prosecutor in tit for tat, in that tit for tat deviates from the witness’s oath to simply provide an honest and accurate answer to each question.

How does a Virginia DUI lawyer work with experts on the way to enhancing prospects for victory?

A DUI lawyer needs to check the expert witness’s interest, availability and billing structure for testifying in court. The lawyer needs to determine whether the governing court rules require disclosing the expert, when to disclose the expert, and what to say in the disclosure. Even when the governing rules do not require disclosing expert witnesses, the defense may still wish to make such a disclosure to assist with enhancing case negotiations, to inform the court of the need for sufficient trial time to present the expert’s testimony, and to counter any efforts by the prosecutor to seek a same-day trial postponement in order to have time to obtain a counter-expert. I have prevented some continuances in the past by informing the judge that I had weeks earlier disclosed to the prosecution and court that a defense expert was arranged to come to trial, and to have the expert witness stand to confirm his presence.

How should my Virginia DUI lawyer present the testimony of experts?

Experts cannot testify as expert witnesses before the lawyer presents the witness’s relevant credentials from the witness stand, and offers him or her as an expert in technical areas X, Y and/or Z. The opposing lawyer gets to cross examine the witness accordingly. For enhancing the firepower of a defense expert witness, a criminal defense lawyer needs to anticipate possible prosecutorial objections to the qualifications defense experts, and determine how to overcome those objections. Common objections by prosecutors against a defense breathalyzer expert might include the extent to which that expert has used the Virginia-modified version of the Intox EC/IR II machine, whether the expert owns the particular breathalyzer model, and how often the witness has testified on the matter at hand. My response is based on the low threshold for qualifying an expert witness under Virginia law, which is essentially whether the expert can assist a layperson in understanding the evidence. A prosecutorial objection that the defense expert has not used a Virginia-modified breathalyzer machine invites my moving to exclude BAC evidence entirely, seeing that the Virginia Department of Forensic Science (DFS) is not expected to make such machines available to defense experts. Owning a breathalyzer machine is not essential for testifying about the machine, at least where the expert has used the machine. Frequency of testifying is not necessary to make one an expert witness. All of the foregoing prosecutorial objections are more related to the weight for the jury or judge to give the expert’s testimony, rather than the admissibility of such testimony.

How should experts testify in criminal court for enhancing their benefit for the defense?

Enhancing the strength of a DUI defense expert’s testimony is not rocket science, and instead involves the following approach. Experts need to testify pursuant to their oath to present truthful testimony, just as any lay witness must do. The criminal defense lawyer can take the wind out of the prosecutor’s sales by proactively asking the expert his or her billing structure, and to underline that the expert is billing for his or her time, and not for testifying favorably for the defense. Well before the trial date, the expert should have been provided the data necessary to formulate an honest and relevant opinion. The expert needs to know the relevant data and evidence cold, so as to fulfill his or her oath to tell the truth, and also for his or her testimony to be relevant and to justify the expert’s fee. As with lay witnesses, experts should not fight the cross-examining prosecutor, but instead simply stick to his or her oath to tell the truth.

Are experts needed when my independent blood certificate of analysis has a favorable testing result?

For Virginia DUI cases involving blood testing, an inexpensive approach for possibly enhancing the defendant’s prosects is to obtain a court order to transfer a sample of the blood drawn from the defendant on the incident date, to a private lab, for independent blood alcohol content (BAC) testing. This is important to assist any case negotiations, to the extent that the independent lab’s BAC testing result is significantly lower than the DFS result, but also if the independent lab’s result provides an argument that the BAC was below the per se DUI or mandatory minimum sentencing threshold, in the event that the DFS BAC result supports otherwise. Virginia statutory law provides the steps to present the independent lab’s certificate of analysis without needing live testimony from the independent lab scientist, even if live testimony is ideal. Virginia Code § 19.2-187. A forensic toxicology expert may be able beneficially be able to explain testing margins of uncertainty, and a lower BAC test by a private lab than the testing result from the DFS.

This is the second of a two-part article. The first part is here

Fairfax DUI lawyer Jonathan L. Katz repeatedly works with expert witnesses for pursuing the best defense against Virginia DUI, felony and misdemeanor prosecutions. Find out what Jon Katz can do for your successful defense, by calling 703-383-1100 to schedule a free in-person consultation with Jon about your court-pending case. 

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