What Questions Do They Ask on a Police Polygraph Test? Unraveling the Mystery
The polygraph, often called a "lie detector," remains a controversial tool in law enforcement. While not admissible in many courts as definitive proof of guilt or innocence, it's still used during investigations. Understanding the types of questions asked during a police polygraph test can shed light on its methodology and limitations. This article will delve into the process and the various question types employed.
The Structure of a Polygraph Examination:
A typical polygraph examination doesn't simply involve asking "Did you do it?". Instead, it follows a structured approach, typically including three types of questions:
1. Irrelevant Questions: These are designed to establish a baseline of the subject's physiological responses. Examples include questions about their name, age, address, or the weather. These seemingly innocuous questions help the examiner determine the individual's normal physiological responses (heart rate, respiration, skin conductivity).
2. Relevant Questions: These are the critical questions directly related to the crime under investigation. They are carefully worded to address the key aspects of the suspected wrongdoing. For example, in a theft case, relevant questions might include:
- "Did you steal the money from the office?"
- "Were you in the office after hours on the night of the theft?"
- "Do you know who stole the money from the office?"
The phrasing of these questions is crucial and will vary depending on the specifics of the case. The examiner aims to create questions that are unambiguous and difficult to deceive.
3. Control Questions: These are designed to elicit a deceptive response from someone who is being truthful about the relevant questions. They address general behaviors that most people would find embarrassing or slightly incriminating. Examples include:
- "Before the age of 21, did you ever do something dishonest to get something you wanted?"
- "Have you ever lied to avoid getting into trouble?"
The examiner compares the physiological responses to the relevant questions with those elicited by the control questions. A larger physiological response to the relevant questions, compared to the control questions, might be interpreted as deception. However, this interpretation is subjective and heavily relies on the examiner's expertise and experience.
Important Considerations:
- No Single "Magic Question": There's no single question that definitively reveals deception. The polygraph analyzes patterns of physiological responses across multiple questions.
- Subjectivity of Interpretation: The interpretation of polygraph results is inherently subjective. Different examiners may reach different conclusions based on the same data.
- Factors Affecting Results: Numerous factors can influence the results, including stress, anxiety, medication, and even pre-existing medical conditions. These factors can produce false positives (indicating deception when the subject is truthful) or false negatives (indicating truthfulness when the subject is lying).
- Legal Admissibility: The admissibility of polygraph evidence varies widely depending on jurisdiction and legal precedent. Many courts do not accept polygraph results as conclusive evidence.
Conclusion:
Understanding the types of questions asked during a police polygraph test provides insight into the process. While the polygraph aims to detect deception, it’s essential to remember its limitations and inherent subjectivity. It’s not a foolproof method, and its results should be interpreted cautiously, even by trained professionals. The legal and ethical implications of using polygraph tests in criminal investigations continue to be a subject of intense debate.
