A DUI charge can involve much more than the results of a breathalyzer or the observations of a police officer. Prosecutors may rely on several types of evidence, including field sobriety tests, video footage, witness statements, chemical testing and reports from law enforcement. Each piece can affect how a case is evaluated.

A DUI defense attorney reviews these details to determine whether the evidence was collected properly and whether it actually supports the allegations. The process can uncover inconsistencies, procedural mistakes or other issues that may affect the strength of the prosecution's case.

The consequences of impaired driving can be serious. According to the CDC, 283 children between ages 0 and 14 were killed in crashes involving an alcohol-impaired driver in 2022, representing 25% of traffic-related deaths among children in that age group. Because impaired driving can have devastating consequences, law enforcement takes these allegations seriously. At the same time, people accused of DUI retain the right to have the evidence against them examined carefully.

What Role Does a DUI Defense Attorney Play in Evidence Review?

A DUI defense attorney begins by examining the circumstances surrounding the traffic stop and arrest. This can include reviewing the officer's written report, determining why the vehicle was stopped and examining what happened between the initial interaction and the arrest.

The attorney may also look at whether officers followed appropriate procedures when administering tests or collecting evidence. Timing can matter, particularly when chemical testing is involved. Questions about calibration, maintenance, administration and documentation may also become relevant depending on the circumstances of the case.

Evidence review is not necessarily about finding one dramatic mistake. Sometimes, several smaller inconsistencies can raise questions about the prosecution's interpretation of events. A DUI defense attorney can compare different records to determine whether they tell a consistent story.

This review also helps determine which evidence may be challenged in court and which evidence may provide useful context for the defense.

How Do Attorneys Evaluate Breathalyzer Test Results?

Breathalyzer results can be an important part of a DUI prosecution, but the number displayed by a device is not necessarily the end of the analysis. A DUI defense attorney may examine how the device was operated, maintained and tested.

Attorneys can review records concerning calibration and maintenance, as well as documentation showing whether the equipment was functioning properly. They may also examine whether the officer followed the required procedures before and during the test.

The circumstances immediately before testing can also matter. Depending on applicable state law and the facts of a particular case, factors such as timing, observation periods, medical conditions or substances in the mouth may be relevant to the reliability of a result.

A defense attorney can also compare breath test evidence with other information from the case. If the reported result conflicts with observations, timelines or other testing, those differences may warrant additional examination.

The goal is not to automatically dismiss every breath test as unreliable. Instead, a DUI defense attorney evaluates whether the particular result was obtained under circumstances that make it accurate and admissible.

What Factors Do Attorneys Consider When Reviewing Field Sobriety Tests?

Field sobriety tests are commonly used by officers who suspect a driver is impaired. These tests may involve following instructions while walking, standing or moving the eyes. Officers may then document behaviors they believe indicate impairment.

A DUI defense attorney reviews how the tests were administered and how the officer interpreted the driver's performance. Instructions should be considered, as should the conditions under which the testing occurred.

Roadside testing does not take place in a controlled laboratory environment. Weather, lighting, traffic, road surfaces, footwear, physical limitations and nervousness can potentially affect a person's performance. An attorney may consider whether any of these circumstances were present.

The officer's report can also be compared with available video footage. For example, an officer might describe a particular movement as evidence of impairment, while video could provide additional context about what actually happened.

These reviews can be especially important when the prosecution relies heavily on field sobriety testing. A DUI defense attorney may identify whether the test was administered consistently and whether the conclusions drawn from it are supported by the available evidence.

In What Ways Can Video Evidence Affect a DUI Case?

Video footage can provide a valuable record of events that might otherwise depend primarily on competing recollections. Many DUI investigations may involve dash cameras, body cameras, surveillance systems or other recordings.

A DUI defense attorney can review footage from the initial traffic stop through the field sobriety tests and arrest. The recording may reveal exactly what an officer said, how instructions were given and how the driver responded.

Video can also provide information that is missing from written reports. An officer's report may summarize a lengthy interaction in only a few paragraphs, while video can show the sequence of events in considerably greater detail.

Attorneys may look for differences between the recording and the written report. If a report characterizes a driver's behavior in a particular way, the footage can be examined to determine whether it supports that description.

Video may also show environmental conditions, physical obstacles or other circumstances that could have influenced field sobriety testing. In some cases, it can support the prosecution's account. In others, it may provide information that raises questions about the interpretation of the events.

For this reason, a DUI defense attorney generally benefits from reviewing available footage rather than relying exclusively on written accounts.

How Do Attorneys Use Witness Statements to Build a Defense?

Witnesses can provide another perspective on what happened before, during or after a DUI arrest. Depending on the circumstances, witnesses might include passengers, people who interacted with the driver before the traffic stop or individuals who observed the vehicle's operation.

A DUI defense attorney may examine witness statements for consistency and credibility. The attorney can compare what witnesses initially reported with later statements and with other evidence in the case.

For example, a witness may describe how a person was behaving before getting behind the wheel. Another witness may have observed the vehicle shortly before the traffic stop. These accounts could provide context that is not included in a police report.

Inconsistencies can also be significant. If two accounts conflict about an important detail, an attorney may investigate why. Likewise, a witness's ability to observe an event can affect the weight given to that testimony.

Witness statements do not automatically prove innocence or establish that a prosecution's evidence is inaccurate. However, they can help create a fuller picture of the circumstances. A DUI defense attorney can determine whether testimony supports the defense, raises questions about the prosecution's version of events or provides useful context for other evidence.

How Can Evidence Review Shape a DUI Defense?

Evidence review allows a DUI defense attorney to examine the entire case rather than focusing on a single test result. Breath testing, field sobriety testing, video, witness statements, and police reports can all provide pieces of information that need to be considered together.

The attorney may identify procedural concerns, inconsistencies or weaknesses that could affect how evidence is used in court. In other situations, the evidence may be strong, allowing the attorney to provide a realistic assessment of the available options.

Ultimately, careful evidence review is an important part of responding to a DUI charge. A DUI defense attorney can assess how the evidence was collected, whether it accurately reflects what occurred, and whether applicable legal requirements were followed. This detailed examination can help the defense determine how to respond to the allegations and present the strongest arguments available under the circumstances. If you've been charged with a DUI, reach out to Shakhan & Wilkerson Law today.