In Oklahoma, driving under the influence (DUI) is a serious offense that can lead to penalties like high fines, jail time, and the suspension of one’s driving privileges. When you’re facing a DUI charge, it’s important to have an experienced attorney who can challenge the evidence presented by the prosecution. A good DUI lawyer in Oklahoma City will have a number of ways to do that.
Challenging DUI Evidence: Techniques That Can Be Used by Your Oklahoma City DUI Lawyer
Pre-Trial Motions
One of the first steps in challenging DUI evidence is filing pre-trial motions. Lawyers use motions to keep evidence out of the trial by arguing that the evidence was obtained in violation of their client’s constitutional rights.
Motion to Suppress Statements
If a defendant was not read their Miranda rights or was coerced into making a statement, the motion to suppress statements would argue that any subsequent statements made should be excluded from trial.
Motion to Suppress Evidence
If law enforcement conducted an unlawful search and seizure, the motion to suppress evidence would argue that any evidence discovered during the search should be excluded from trial.
Challenging Field Sobriety Tests
Field sobriety tests, such as the Horizontal Gaze Nystagmus (HGN) test and the Walk and Turn test, are commonly used by law enforcement officers to gather evidence of intoxication. Oklahoma lawyers can challenge the reliability of these tests by arguing that they are not scientifically valid or that the officer administering the test did not follow proper protocols. For instance, if an officer did not provide clear instructions or failed to allow the defendant to complete the test, the results could be deemed inadmissible.
Questioning Expert Witnesses
In DUI cases, expert witnesses such as toxicologists or Breathalyzer technicians are often called to testify about the results of chemical tests or the operation of the Breathalyzer machine. Lawyers can both bring their own experts to challenge the prosecution’s version of events and can conduct a cross-examination to challenge the expertise of the prosecution’s witnesses and to highlight any flaws in their methodology or conclusions. By attacking the credibility of the prosecution’s expert witnesses and bringing their own witnesses, lawyers can weaken the prosecution’s case and create reasonable doubt.
Analyzing Blood and Breath Test Results
Blood and breath test results are usually critical pieces of evidence in DUI cases, and your Oklahoma City DUI lawyer will take a close look at these results, examining the chain of custody, questioning the accuracy of the testing equipment, and analyzing the sample collection and storage procedures. Common challenges include:
Chain of Custody Issues
Lawyers may argue that there were gaps or inconsistencies in the chain of custody, which could compromise the integrity of the sample.
Equipment Malfunctions
Your lawyer may argue that the testing equipment was not properly calibrated or malfunctioned, resulting in inaccurate test results.
Inadequate Sample Collection or Storage
Lawyers can also sometimes argue that the sample was not properly collected or stored, which could result in inaccurate test results or contamination.
Challenging Police Procedures
Law enforcement officers are required to follow specific procedures when conducting DUI investigations, so your lawyer will carefully review police reports and observe the officer’s behavior to identify if there were any violations of these procedures. You are required by law to submit to a Breathalyzer test (having a driver’s license in Oklahoma gives the police your de facto permission to conduct this test), and officers don’t need to read you your rights to administer this test.
However, if they wish to take a blood test or urine test, or if they intend to arrest and question you, you must be read your rights. If this didn’t happen, the procedure wasn’t followed. Another common area to challenge is that the officer lacked probable cause to stop the vehicle or that the stop was otherwise unlawful. This approach can be particularly effective if there is evidence that the officer deviated from standard procedures or has a history of improperly conducted DUI arrests.
Cross-Examining the Prosecution’s Witnesses
During a trial, your lawyer can use cross-examination to challenge the testimony of prosecution witnesses. Your lawyer may also be able to use prior, inconsistent statements made by witnesses to impeach their credibility and undermine their testimony. For an expert witness, your lawyer may call into question the qualifications of prosecution witnesses, such as their education, experience, and expertise.
Challenging Eyewitness Testimony
Eyewitness testimony can be a critical component of a DUI prosecutor’s case; however, eyewitness identification is known to be one of the most unreliable forms of evidence. Your lawyer will see if there are inconsistencies in the testimony and investigate whether environmental or personal issues could have interfered with their ability to really see what happened.
Using Alternative Explanations for Observed Behavior
One effective defense technique is to offer alternative explanations for the defendant’s behavior or appearance that led to the DUI charge. Your lawyer might argue that factors such as fatigue, medical conditions, or environmental conditions like poor lighting or uneven ground could have affected the field sobriety test results. For instance, certain medical conditions can mimic the signs of intoxication, such as diabetes, which can cause slurred speech or an unsteady gait due to low blood sugar levels.
Presenting Character Witnesses
In some cases, character witnesses can be used to testify about the defendant’s behavior and state of mind before the arrest. These witnesses can provide an alternative narrative, suggesting that the defendant was not intoxicated. For instance, friends or colleagues who were with the defendant shortly before the arrest can testify that the defendant did not consume any alcohol or that they did not observe any signs of impairment.
Arguing Rising Blood Alcohol Content (BAC)
Another defense strategy is to argue that the defendant’s BAC was below the legal limit while they were driving but rose to an illegal level by the time the test was administered. This can happen if the defendant consumed alcohol shortly before driving, as it takes time for alcohol to be absorbed into the bloodstream. Your lawyer can present evidence and expert testimony to support this argument, potentially casting doubt on the accuracy of the BAC results at the time of driving.
Examining Video Evidence
Many DUI arrests are recorded on police dash cams or body cameras, and a lawyer can review this footage to ensure that the officer’s conduct and the defendant’s behavior are consistent with the officer’s report. Video evidence can be crucial in demonstrating whether the field sobriety tests were administered correctly and whether the defendant exhibited signs of intoxication. Any discrepancies between the video evidence and the officer’s testimony – even if they don’t directly relate to your blood alcohol level – can potentially be used to undermine the evidence presented by the officer.
Challenging DUI evidence takes expertise in the law, experience in these cases, and devotion to the ideal that everyone is innocent until proven guilty. Through pre-trial motions, challenging field sobriety tests, questioning expert witnesses, analyzing blood and breath test results, challenging police procedures, and cross-examining prosecution witnesses, a good defense attorney can do more than you might think. If you’ve been charged, contact us at Cannon & Associates right away so we can get to work protecting you.