The cost of lie detector testing varies according to your location, the time you need the test by or notice you are able to give and the complexity of the test and the issues around the need for the test.
In general, lie detector testing within the UK costs between £350 and £500 per test.
Different providers charge different amounts and this may be due to various reasons; some companies may be very new to the field or struggling to find business and may offer lower pricing to attract custom and to reflect their inexperience. It could also be that a company has purchased cheaper or lower quality instrumentation or do not renew and update this on a regular basis; this will obviously lower their overhead costs and allow them to charge less for a lie detector test.
Some polygraph test providers only cover small areas meaning that they have low expense costs and again can charge less to the end user for a polygraph examination. The lower test cost might also be reflective of a less thorough approach to the testing process which means the company or examiner are investing less of their time in this and can charge a reduced rate as they can fit more tests in per day.
Some companies will be at the more expensive end of the spectrum; this could be reflective of the quality (and therefore higher price) of the equipment they use and how often they update and renew this. It could also be indicative of how thorough they are (being thorough means taking the time to speak to customers in more detail, to invest the effort and thought needed to correctly formulate the question set and undertake the test itself and to be diligent and detailed in the analysis of data). Time obviously costs money so this attention to detail and adherence to correct polygraph principles could come at an increased cost.
Some companies cover large areas or even the whole of the UK; there is a shortage of polygraph examiners in the UK and this means the examiners often travel a great deal to provide testing in all locations. Whilst there may be an office for the company providing the service within the local area, the examiner themselves may not be local and would have incurred significant expense travelling to the location convenient to the customer and may also need to pay for overnight accommodation etc and this will also be reflected in the end price of the lie detector test. In this way, your location can impact on the cost of your test.
The complexity of the test you have requested or the issue behind the need for polygraph examination can also result in a slightly higher price being charged for the test; the wording and language used within questions, as well as the formatting of the test set is essential to achieving valid and reliable data and, therefore, accurate results. If your issue or test questions are particularly complex, it will take a greater amount of time and involvement from the examiner to correctly write and format the test and the extra time needed to do this can result in an increased cost.
If you need a lie detector test at very short notice this may be difficult for the test provider and examiner to accommodate, and they may have to re-arrange other tests or the analysis of other test results in order to provide this for you. The company may have to pay the examiner an increased fee to attend at short notice if they work on a sub-contracted or independent basis. This can all again result in an increased fee.
Lie detector tests (or as they are otherwise known, polygraph examinations) adhere to a specific model of testing. The polygraph examiner themselves will chose the model they prefer to use based on their own school of thought, the research and evidence base behind a particular model or how well suited a particular model is to determining deception within a specific issue.
These models only allow for a certain number of questions to be asked about the specific issue within the test format; the most common number being three. If you wish to ask more than three questions you may need to request more than one test. If these are being held at the same time and same location it is likely that the polygraph company will be able to offer you a discount on the second test.
This may also apply if you wish to address more than one issue; lie detector test models used can be for single facet tests (eg, did you steal the £10?) or some models can be for multi-faceted tests (eg, did you steal the £10? Did you have any involvement in the theft of the £10? Do you know who did steal the £10?).
The company providing your test will be able to advise whether they use a model which enables multi-facet testing or only single facet testing and you may need to book a second test if the model they use can only support single facet testing. The company will have good reason behind their choice to employ the lie detector test model that they use and it is important that they adhere to the principles behind the model. Again, it is likely they will be able to offer a discount on the second test if they are unable to address all your questions in the first.
If you wish to obtain the answers to questions about unrelated issues (eg. Have you had sexual intercourse with anyone other person during our relationship? AND Have you ever posted information online about me that was derogatory?) you will need to have two separate tests as lie detector tests need to focus on a specific event or issue and the formatting and order of test questions is built around this to obtain valid and accurate results.
You would require one test about a person being unfaithful during your relationship and one test about them posting inappropriate or harmful content about you online. Similarly to the above, it is likely that a lie detector test provider will offer a discount if both tests are to be sat at the same time and location.
Caution is advised against taking the cheapest lie detector test you can find; there are likely to be reasons why the test is the cheapest around.
Polygraph examination is an in depth and complex process and, if done properly, utilises expensive instrumentation and requires a great deal of time and attention to detail. Whilst there is no need to book the most expensive test you can find, and this is by no means indicative of the quality of the product you receive, it is worth considering how significant the results of the test will be to you and your life, and the importance of ensuring that you obtain an experienced and invested professional to undertake this for you.
Most polygraph examiners will be happy to explain the basis for the fee they are charging if you feel unsure or confused and also to talk you through what is involved in the entire polygraph process if this is helpful to your decision making when booking a lie detector test.
