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How Criminal Defense Lawyers Challenge Evidence

Drug Evidence
How Criminal Defense Lawyers Challenge Evidence

How a Criminal Defense Lawyer Challenges Evidence

The criminal justice system relies heavily on scientific evidence to reach decisions in criminal proceedings. More often than not, the quality and quantity of criminal evidence will dictate whether a case results in a conviction. Unfortunately, the accuracy of such evidence is not always certain. From bias to human error, evidence can be reliable for a wide range of reasons.

Because forensic techniques are constantly evolving, there is no guarantee that methods are up-to-date, as they could be inaccurate compared to more modern approaches. In some cases, experts or laboratories may have limited knowledge or be swayed by personal biases, leading to inaccuracies in criminal evidence.

Failing to challenge unreliable evidence can jeopardize the accused person’s freedom, hard-earned reputation, and future. Fortunately, our accomplished Oakland criminal defense lawyer has a proven track record of questioning assumptions and challenging the validity of scientific evidence.

Keep reading to learn why our nationally-renowned team is brave enough to question the science and the importance of challenging unreliable evidence in criminal cases.

Brave Enough to Question the Science

Evidence can take various forms in criminal court proceedings. Types of scientific evidence can vary depending on the charges in question, the unique circumstances of each case, and other extenuating factors pertaining to the criminal offense.

Common types of criminal evidence in California include:

  • Written statements
  • Expert testimonies
  • Eyewitness accounts
  • Audio or video footage
  • Photographs or images
  • Medical documentation
  • Any objects relevant to the crime

What Makes Criminal Evidence Inadmissible?

In some cases, evidence can be declared inadmissible in criminal proceedings. This occurs when certain evidence does not fulfill the requirements established under the law. Common examples of evidence inadmissibility include:

  • Evidence obtained through illegal means (such as unreasonable searches and seizures defined in the Fourth Amendment)
  • Evidence that has been improperly handled, tampered with, or tainted
  • Irrelevant evidence that is unrelated to the case at hand
  • Evidence that may lead a jury to make an improper decision based on prejudice or bias
  • Hearsay evidence from someone who did not witness the event in question
  • Testimonies from unqualified witnesses
  • Inadmissible documents (such as illegally obtained texts, emails, or other digital records)
  • Confessions given under duress, coercion, or false pretense

Keep in mind that the judge gets the final say in determining whether or not the evidence is admissible or not. Potentially unreliable evidence will be evaluated for its credibility and relevance to the criminal case in question.

Challenging Scientific Evidence in Criminal Cases

Criminal defense attorneys have a responsibility to ensure their clients receive a fair trial. To do so, they must question any evidence presented in court and work to disprove any unreliable evidence against their client, as even small flaws in seemingly fortified evidence can drastically alter the outcome of a criminal case.

How Can My Lawyer Challenge Criminal Evidence?

There are many ways that criminal defense lawyers can dispute scientific evidence in court. Chosen methods will vary based on the specific nature of your case, state-specific laws, and other key factors.

Below are some common ways that criminal defense attorneys challenge the science in criminal cases:

  • Analyze data to identify errors and biases
  • Uncover discrepancies in testimonies and witness accounts
  • Examine the methods used for evidence collection and storage
  • Obtain statements from licensed experts to back claims when needed

Common Inaccuracies in Criminal Evidence

Scientific evidence plays an important role in criminal courts, but for justice to be served, its accuracy must always be questioned and challenged by those involved in the proceedings. Luckily, our nationally-renowned criminal defense lawyer has a longstanding reputation for quickly and aptly identifying problematic evidence in a range of criminal cases, from DUI defense to drug crimes to domestic violence.

Our firm has extensive experience challenging commonly questioned types of evidence in criminal law, including:

DNA & Fingerprinting

While DNA and fingerprinting can be reliable scientific evidence in criminal cases, neither is immune to inaccuracies. In some cases, errors in collection and analysis methods can lead to unreliable results. Inaccuracies in DNA evidence can occur due to contamination or degradation of the sample or poor handling techniques, such as not taking precautions to prevent cross-contamination between samples. DNA samples can also degrade over time, producing inaccurate readings.

Fingerprinting can produce inaccurate results in the form of misidentification, which in turn may lead to wrongful convictions in court. This can occur due to smudged or distorted prints or certain environmental factors, such as extreme temperatures or moisture. Human error and personal bias can also play a role when it comes to unreliable DNA and fingerprinting evidence.

Lie Detectors

Lie detectors, also known as polygraph tests, are commonly used in criminal cases. Like other types of scientific evidence, lie detectors can be unreliable in criminal court—but there are some instances where lie detector results aren't credible and should likely be dismissed from the criminal case in question.

While the results of a lie detector test can be compelling and appear to provide accurate insights into a person's mental state, the scientific accuracy of these tests is heavily disputed. They can be easily influenced by external factors, such as stress or fear, and lead to false positives or negatives. This means that some lie detector test results aren’t reliable as valid scientific evidence in criminal court, making it all the more important to consult with a qualified criminal defense attorney who understands how to recognize and challenge unreliable evidence to ensure a fair trial.

Medical Documentation

Medical records or documentation is a common and important source of evidence in criminal court that can play a significant part in establishing guilt or innocence. However, this evidence isn’t always reliable. For example, if the medical documents in question are incomplete, they may not be admissible as evidence. Similarly, if the documents aren’t up-to-date or have been altered in any way, they can be challenged and dismissed from the case as unreliable evidence.

Chemical Test Results

Breathalyzer tests and blood alcohol content (BAC) tests are often used as key evidence in DUI cases and related proceedings. However, this doesn’t necessarily mean that the test results are foolproof. In some cases, these tests can be unreliable due to a variety of factors, such as:

  • Improper calibration or administration of the test
  • Human error when interpreting results
  • Environmental conditions

Certain circumstantial factors may also interfere with the accuracy, of a breathalyzer, such as mouthwash containing alcohol, certain medical conditions and prescriptions, and even variances in diet. Breathalyzers can be especially unreliable when used on individuals with asthma or diabetes, as the presence of acetone in their breath can result in false readings.

It’s also possible for a person's BAC to rise after submitting a breath test due to continued alcohol absorption. If the sample is taken too long after drinking, the results may no longer accurately reflect the level at the time of driving. It’s imperative to secure strong defense from an experienced attorney who can challenge any faulty test results after a DUI or related charge, as this can drastically alter the outcome of your case.

Radar & Lidar Devices

Radar devices are commonly used by law enforcement officers to detect and measure the speed of vehicles. However, they can be unreliable evidence in criminal cases due to a variety of factors. For example, radar devices can be influenced by interference from nearby objects like trees or buildings. Additionally, the accuracy of these devices can be compromised if they are not properly calibrated or maintained according to manufacturer specifications.

Even if the device is properly calibrated, its readings can be affected by incorrect techniques when being operated by the law enforcement officer. Inaccurate readings can occur if the officer was too far away from the targeted vehicle or didn’t have a clear line of vision at the time. Certain environmental conditions, such as wind or rain, can also affect radar device accuracy and overall reliability in criminal cases.

Contact the Bay Area’s Top Criminal Defense Firm Today

Evidence in a criminal case can mean the difference between spending years in prison and walking away as a free person. When it comes to disproving scientific evidence, the Law Office of Nabiel C. Ahmed utilizes a comprehensive approach, allowing us to quickly and effectively challenge any unreliable evidence against you. By scrutinizing all aspects of your case, our knowledgeable legal team can quickly identify discrepancies in witness accounts, testimonies, and other forms of criminal evidence.

For well over a decade, our founding attorney has used his practiced legal eye to identify and dismiss scientific evidence that otherwise might have resulted in life-altering legal penalties for the accused in California. With thousands of cases handled in Oakland and beyond, you can count on us to protect your future and defend your right to a fair trial. Reach out to our office today to learn how we can collaborate with you to achieve the justice you rightfully deserve.

If you’re facing criminal charges in the Bay Area, you need strong representation to defend your rights. Call (510) 907-6600 to schedule a consultation.