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Should You Take a Polygraph? Lie Detector Tests in Texas Sex Crime Investigations

Should You Take a Polygraph? Lie Detector Tests in Texas Sex Crimes

Published: Apr 30, 2024 in Criminal Defense, Sex Crimes

Few tools in the criminal justice system are as controversial and misunderstood as the polygraph test. Commonly referred to as a “lie detector,” the polygraph is frequently employed in high-stakes sex crime investigations across Texas.

Despite their widespread use, the results of these tests are not generally admissible in court. Yet, they can significantly influence an investigation. Here, we’ll delve into the role of polygraph tests in Texas sex crime investigations, exploring their applications, legal status, and the decisions that accused individuals must face.

Polygraph Tests in Texas

With decades of experience defending clients accused of sex offenses, and as someone familiar with Texas law and the psychological strategies employed in sex crime investigations, Attorney Ned Barnett wants you to understand your rights and weigh your options carefully.

What is a Polygraph Test?

A polygraph or lie detector is a device used to measure and record physiological indicators while being asked a series of questions. The goal is to detect physiological changes that could indicate the subject is not truthful.

How Do Lie Detectors Work?

A polygraph monitors several bodily responses, such as blood pressure, pulse, and respiration. When a person answers, the idea is that being deceptive will elicit a stress response, creating noticeable changes in these vital signs. For example, an increased heart rate or higher blood pressure might be interpreted as signs of lying. Additionally, the polygraph also measures skin response, which tracks the skin’s electrical conductance. This can fluctuate with sweat—supposedly linked to the stress of being deceptive.

These responses are recorded and analyzed, indicating whether the person is deceptive, truthful, or inconclusive. The operator of the polygraph, who is trained to read these results, plays a crucial role in interpreting the data and determining the outcome of the test.

Are Polygraphs Accurate?

It’s critical to note that interpreting polygraph results is not a straightforward science. Numerous factors can affect a person’s physiological responses, including nervousness, fear, confusion, or other emotional states unrelated to lying.

This ambiguity is one reason why polygraphs are viewed with skepticism, including in Texas.

Admissibility of Polygraph Tests in Texas

The Texas judicial system treads cautiously when it comes to using polygraph tests in court. According to the Texas Rules of Evidence, Rule 702, which governs the admissibility of expert witness testimony, polygraph tests have traditionally been viewed as failing to meet the reliability standards for scientific evidence. While polygraphs are used by law enforcement during investigations, the courts have largely rejected them as definitive evidence due to questions about their accuracy and reliability.

The United States Supreme Court has also recognized the potential for inaccuracy with polygraphs. In United States v. Scheffer, the court acknowledged that the scientific community remains extensively divided on the reliability of polygraph techniques. This ruling reinforces that polygraph results are not reliable enough to be considered conclusive evidence.

Under Rule 403, Texas courts adhere to a standard that demands sufficiently reliable scientific evidence. This rule allows courts to exclude evidence if its probative value substantially outweighs the risk of unfair prejudice.

So, given the controversies surrounding polygraphs, their results are often deemed to pose more risks than benefits. As such, while polygraph tests might play a role during the investigation phase of a sex crime, their significance is diminished once a case proceeds to trial. This nuanced view of lie detectors is an essential consideration for anyone contemplating submitting to a polygraph test.

The Use of Polygraphs in Texas Sex Crime Investigations

Polygraph tests are a standard tool employed by Texas law enforcement in sex offense cases. Typically, these tests are requested after an initial statement has been taken from the suspect, particularly in cases where the suspect denies the allegations.

The request for a polygraph often comes with the implication that passing the test could substantiate the suspect’s claims of innocence. But it’s crucial to understand that law enforcement may use the polygraph as much for its psychological impact as for its ability to discern the “truth” about what happened.

The Psychological Role of Polygraphs

A polygraph’s role in sex crime investigations goes beyond corroborating a suspect’s account. It also provides an opportunity to question the individual and provoke anxiety-induced responses.

For example, if you’re accused of sexual assault, the police may suggest that you submit to a polygraph to clear up a possible misunderstanding. But the officers are banking on when confronted, you might either admit guilt or exhibit physiological responses that suggest deception. Such an outcome could pave the way for further questioning and formal charges.

How Do Lie Detectors Affect Sex Crime Investigations?

As you can see, simply administering a polygraph can shift the dynamics between a person of interest and law enforcement, potentially overshadowing other evidence. It’s a high-stress situation, and even if the polygraph results are not admissible in court, the reactions and subsequent statements made in connection with the test carry considerable weight.

For instance, consider a scenario where you are a person of interest in a rape case and agree to a polygraph test. During the test, you may exhibit signs that are interpreted as deceptive. The interpretation can create a confirmatory bias, where officers may give greater credence to information that aligns with the test’s findings, even if exculpatory evidence exists. This could lead law enforcement to focus more intently on you, possibly to the exclusion of other leads or evidence.

Why Would Someone Accused of a Sex Crime Agree to a Polygraph?

The decision to undergo a polygraph should not be taken lightly.

Deciding to submit to a lie detector often stems from the belief that a passed test could sway investigators before formal charges are filed. This could be effective if there is little to go on besides the victim’s account and a lack of physical evidence. In such cases, a polygraph report indicating truthfulness could establish credibility and assist negotiations.

The Benefits & Risks of Taking a Polygraph

When faced with a sex crime accusation and considering a polygraph test, weigh these key points:

The Risks

  • False positives could misrepresent your truthfulness, leading to more scrutiny.
  • Test-induced stress might result in deceptive-seeming responses, affecting case direction.
  • A failure may strengthen the prosecution’s determination, even with conflicting evidence.

The Benefits

  • Passing could dissuade law enforcement from filing charges.
  • May lead to charge reduction or more favorable pleas.
  • Could convince the prosecution to drop the case altogether.

Polygraphs for Sex Offender Monitoring

Polygraph tests are not just tools for the investigatory phase of sex offenses. They also play a role in monitoring individuals on probation or parole for sex offenses. Under 18 U.S.C. § 3563, courts can mandate that sex offenders undergo not just psychological treatment but also periodic polygraph testing to verify compliance with their probation or parole.

This level of supervision is predicated on the belief that polygraph testing can deter future offenses. The results of these tests can be crucial for probation officers to make informed decisions on the necessary level of supervision, making polygraph testing a vital part of post-conviction management for sex offenders in Texas.

Work with a Lawyer When Considering a Polygraph

Before consenting to a polygraph test as part of a sex crime investigation, it’s imperative to consult a criminal defense lawyer. An experienced attorney can provide critical insights into how the test could influence your case and, perhaps more importantly, help you understand your rights. Your lawyer will consider the specific circumstances of your case, such as the nature of the allegations and the evidence, to offer informed guidance on whether a polygraph could be more harmful than helpful.

Additionally, your attorney can negotiate the terms under which the polygraph would be conducted, which could offer more control over how the results are used.

A defense attorney’s role also extends to managing the risks associated with taking a polygraph test. They can help prepare you for the test, advising on the types of questions that may be asked and how to remain calm under pressure. Legal counsel ensures that any polygraph test is conducted to protect your rights, advising you on how to respond if the test results are not in your favor. They can also argue against the overemphasis of polygraph results, especially when other evidence should take precedence.

Consider a Private Polygraph with Your Attorney

Additionally, your attorney can negotiate the terms under which the polygraph would be conducted, potentially arranging for a private polygraph, which could offer more control over how the results are used.

While law enforcement-administered polygraphs might be seen as inherently flawed, an attorney-facilitated polygraph can provide some protection. A private polygraph test will be viewed as unbiased and could be used to persuade the prosecution of your innocence or, at the very least, cast doubt. The results, whether favorable or not, remain confidential and can be used at your discretion.

Accused in Houston? Contact Attorney Ned Barnett

While polygraph tests remain a controversial and complex part of Texas sex crime investigations, their implications are profound. Whether it poses a risk or serves as a strategic advantage, guidance from a skilled lawyer is indispensable in deciding if undergoing a polygraph test aligns with your best interests.

Texas attorney Ned Barnett champions the rights of the accused and has considerable experience handling sex crime cases in Houston, Texas. He knows how polygraph tests impact sensitive situations and what it takes to defend yourself successfully.

If you’re facing sex offense allegations or have been charged with a crime, call The Law Offices of Ned Barnett today at (713) 222-6767. We offer free and confidential case evaluations where we’ll discuss your options and guide your next steps.