Expert Witnesses in Howard County DUI Cases
While expert witnesses in DUI cases are pretty rare, it can happen in certain cases. For example, an accident reconstruction expert may speak if there was an accident. Additionally, in some cases an expert in the medical field will testify, especially if a blood draw was done or if the defendant has a unique medical condition that requires testimony from some kind of doctor. However, regardless of what type of expert may be used, it is important to have a Howard County DUI lawyer on your side to determine if an expert witness is necessary for the defense and to cross examine any experts put forth by the prosecution.
Types of Experts Used in DUI Cases
The horizontal gaze nystagmus (HGN) test needs to be testified to by an officer who is certified as an expert in the administration of the test. The test itself is incredibly specific, most people understand it to be a test following a pen or light stimulus in front of their eyes approximately 12 inches away. Conducting the test is incredibly detail-driven and is generally completed in an uncontrolled environment outdoors by a police officer, not a medical professional. It sometimes can be argued that not even an optometrist would be responsible for giving the test, only a neurologist should be.
That test is so complicated that it requires the prosecution to give testimony to be specific to the performance of the test by an expert, generally the state attorney that knows how the officer was trained.
Other prosecution experts would be in the medical field, especially if a blood draw was done and they want someone to testify as an expert on the scoring of the blood test and how it was done. This generally comes from the forensic lab that ran the test, as well as the phlebotomist or nurse involved in the blood draw.
Role of Testimony
It is important to have an attorney with expert connections so they might discuss all of the elements that might be disputable, and have that witness stand trial and change the outcome of a case. For example, indigestion, and GERD can cause an unusual effect in the body surrounding a DUI case. This can be testified to by an expert at court.
Everybody is uniquely different and human bodies are uniquely different. If there is something that can be scientifically relied on for the client, the expert needs to get that science in as evidence.
Each party is responsible for calling their experts as well as informing the other side who will be called to testify. The expert should be ready to testify so their testimony is good, clean, and crisp so the judge gives it the proper weight. Without the proper weight, it will not receive the proper attention as an expert opinion. If there is a dispute for example, regarding the testing, results of the test, or condition of the client, then it is important to have the weight relied on by the judge to weigh favorably in the defendant’s side.
Refuting an Expert
The best way to refute or challenge the claim of the expert on the HGN test is to have them conduct the test as they are supposed to right in the courtroom. The defense attorney can request that the expert do the test on the defense attorney themselves. As they conduct the test, the defense attorney will question them on every aspect of the test and compare the answer to the National Highway Transportation Standardized Field Sobriety Testing book. If they vary even the slightest, the test cannot be relied upon because it was not done specifically and that book says it must be specifically done.