What Questions Do They Ask on a Police Polygraph?
A polygraph, also known as a lie detector test, is a crucial tool used by law enforcement agencies to detect deception and verify the truthfulness of a person’s statements. The test is based on the principle that a person’s physiological responses, such as heart rate, blood pressure, and breathing, will change when they are telling a lie. In a police polygraph examination, the examiner asks a series of questions, both relevant and irrelevant, to compare the person’s responses and detect any inconsistencies.
Relevant Questions
The most critical part of a polygraph examination is the set of relevant questions, which are designed to focus on the specific issue or crime being investigated. These questions are carefully crafted to elicit a truthful response from the examinee, while also detecting any deception. Relevant questions are usually specific, detailed, and related to the alleged crime or incident.
Here are some examples of relevant questions that may be asked during a police polygraph examination:
- Direct questions: Did you commit the crime? Did you witness the incident?
- Specific questions: Did you see the suspect on the night of the robbery? Did you take the stolen goods?
- Event-based questions: Did you attend the meeting? Did you have any conversations with the victim?
- Behavioral questions: Did you notice anything unusual? Did you hear any suspicious noises?
Irrelevant Questions
Irrelevant questions, also known as control questions, are designed to elicit a strong physiological response from the examinee, which is then compared to their response to the relevant questions. Irrelevant questions are typically unrelated to the crime or investigation.
Here are some examples of irrelevant questions that may be asked during a police polygraph examination:
- General questions: Have you ever told a lie? Have you ever broken the law?
- Personal questions: Do you have any health problems? Have you ever been in a relationship?
- Neutral questions: Have you ever been to a movie? Have you ever eaten at a restaurant?
Control Questions
Control questions are a type of irrelevant question that is designed to elicit a strong physiological response from the examinee. These questions are typically related to the examinee’s personal experiences or habits.
Here are some examples of control questions that may be asked during a police polygraph examination:
- Experiential questions: Have you ever broken a bone? Have you ever had a tattoo?
- Habitual questions: Do you smoke? Do you have a pet?
Comparison of Responses
After asking the relevant and irrelevant questions, the polygraph examiner analyzes the examinee’s responses to identify any inconsistencies or changes in their physiological responses. The examiner compares the examinee’s responses to the relevant questions with their responses to the irrelevant questions.
Here are some examples of how the examiner might analyze the responses:
- Increased physiological response: If the examinee shows an increased physiological response to a relevant question, it may indicate that they are hiding something or telling a lie.
- Consistent physiological response: If the examinee shows a consistent physiological response to all questions, it may indicate that they are telling the truth.
- Inconsistencies: If the examinee shows different physiological responses to the same question, it may indicate that they are telling different versions of the truth.
Table: Polygraph Question Types
| Question Type | Description | Example Questions |
|---|---|---|
| Relevant Questions | Focus on the specific issue or crime being investigated | Did you commit the crime? Did you witness the incident? |
| Irrelevant Questions | Unrelated to the crime or investigation | Have you ever told a lie? Have you ever broken the law? |
| Control Questions | Designed to elicit a strong physiological response | Have you ever broken a bone? Do you smoke? |
Conclusion
In conclusion, a police polygraph examination involves asking a series of questions, both relevant and irrelevant, to detect deception and verify the truthfulness of a person’s statements. The examiner analyzes the examinee’s responses to identify any inconsistencies or changes in their physiological responses, and uses this information to make an informed decision about the person’s guilt or innocence. It is essential to note that polygraph examinations are not infallible and should be used in conjunction with other evidence and investigative techniques.
