There are several answers to this question as there are various forms of police polygraph examination that it could be referring to:
- In the United States of America, in some states, applicants to law enforcement employee roles such as that of a police officer undertake a polygraph examination as part of the application and interview process so a police polygraph test could be referring to this situation.
- In the United States of America, polygraph examination results and reports are admissible to criminal courts as evidence (unlike here in the UK where lie detector test results and reports are not accepted within criminal courts at this time). Police departments utilise polygraph examinations within their investigations to interview suspects to determine the probability that they were the culprit or involved in the crime being looked into in any way. The question may be referring to this form of police polygraph test.
- The third option that the question may be referring to is the current limited use of polygraph examination within UK policing and the probation service; Polygraph examinations have been used with success within the UK national probation service since 2007 for high-risk sexual offenders on release to monitor compliance with their license conditions. These were initially undertaken on a voluntary basis but, since 2014, these have had the option to be mandatory and included as such on an offender’s release conditions. Perpetrators have been recalled to prison as a result of further investigation following a polygraph examination having been undertaken.
Similar measures are being considered within the Domestic Abuse Bill to be utilised with convicted high-risk domestic abuse perpetrators, and a 3 year pilot study arranged for offenders to engage with polygraph examination on a non-mandatory basis as part of their license and release conditions.
The Counter Terrorism Bill has also made recommendations to apply mandatory polygraph testing to individuals who have been convicted of acts of terrorism or offences related to this; this recommendation was in response to the London Bridge Attack that occurred in 2019 in which Usman Khan murdered 2 people and caused significant injury to a further 3. Khan was on out on licence wen he committed this atrocity.
There is some debate, insinuation and suggestion around other less publicly known uses of polygraph examination by the police in the UK but this is unconfirmed.
This article will try to address the title question in regard to all 3 potential situations of police utilising polygraph examination within a professional capacity.
Firstly, when identifying which questions will be contained within a “police polygraph test” there are certain rules that apply to all polygraph testing and that form the basis of the test itself following decades of research, experimentation and development focused on improving lie detector test accuracy; there are different models of testing that different polygraph examiners use due to their own school of thought, rationale around the level of research and evidence base incorporated into that model or the specific issue and questions as well as the number of issues and questions that require addressing within the test. However, there are certain similarities and consistencies within any polygraph examination model.
All polygraph examinations will contain various types or categories of questions with the test set; the test will not just consist of directly asking the questions about the issue that needs clarification. There are formats of questioning that have specific structures or order of questioning implicit to the correct application of the model and this is designed to create the optimum psychological environment to achieve indicative responses from the subject; to promote tension and determine saliency or significance more clearly.
These question sets vary from model to model in terms of language used and exact nature or purpose of the questions, but all tests will include some form of introductory question that allows for self-report by the subject as to whether they understand the test itself and whether they intend to be honest. The test will also include some form of irrelevant questioning which includes the use on trivial and non-triggering questioning around, for example, the day of the week, the weather, a physical item in the room that can be observed. There will also be asked some form of control or comparison questions; these are somehow linked or connected to the incident or behaviour that is being addressed within the polygraph examination but do not specify and are more general. They often include exclusionary statements to prevent response in regard to the actual matter at the heart of the test by drawing parameters that remove the time, date or location, for example, of the incident being investigated. Finally, there will be the questions that overtly and purposefully address the issue that the test has been arranged to clarify and that seek to determine deception or honesty concerning the subject’s claims for his or her own behaviours around this.
In terms of the polygraph examination used within applicant and interview procedures for candidates wishing to become a police officer within the US, these tests will include questions around the application form they have completed and how honest they have been within this and the statements they have made, questions around their history and past behaviours and any misdemeanours or concerning events that they have not been arrested for, or associations pertaining to this. They will be asked about alcohol and drug use, as well as their driving history and their financial situation and past. The polygraph examination included in part of the US police interviewing process will also look at the candidate’s general history and will ask about the school they attended and any military history. The test will also seek to clarify if the candidate has committed offences or offending behaviour in any other countries in the world where their record searching would not extend to.
In regard to the use of polygraph examination by police in America to interview and investigate criminal suspects, and the submitting of the results and reports for these to court as evidence, the questions used will be specific to the incident and crime being alleged and so it is not possible to state what will be asked, beyond following the structural requirements of a polygraph test question set as stated above. Every set of questions for lie detector testing needs to be uniquely written and formulated to address the precise incident and behaviours pertinent to the matter at the heart of that test.
Lastly, in reference to polygraph examination being used within UK policing and probation services for convicted offenders who are on release and being monitored through licence conditions, it is again not possible (beyond the above stated question model formatting) to advise of the specific questions that will be asked. These will pertain to the individual, their own previous convictions and their current situation and relationships. The questions will most likely include asking about the behaviours they have undertaken whilst on licence and out in the community and may refer to substance use, living arrangements, contact with others, employment and support they have engaged with if this is also recommended within licence conditions. The questions will be specific to the offender’s historic behaviours and concerns around this and will seek to identify any breaches of licence or any actions or intentions that indicate they have re-offended or are at high risk of re-offending.
