If your business becomes subject to theft or fraud, it can be devastating, and might even lead to total organisational collapse. That’s why it’s vital that you have employees who are honest and trustworthy. A lie detector test can be a useful investigative tool to use if you suspect that a colleague or employee is behaving deceitfully. This article will clarify whether employers in the UK can use lie detector tests, and the best practice by which to do so.

What are lie detector tests?

Despite sounding like a one-size-fits-all solution, there are different lie detector tests to choose from. The better-known tests are polygraphs, which monitor the physiological response of the person attached to the machine. By measuring changes in the body, polygraphs work to measure the effect of a lie on the person being tested.

That alternative, used by M19 Solutions, is the ‘Eye Detect’ system, a tamper-free, incorruptible test. Non-invasive and discreet, our expert administrators hook examinees up to a computer, which uses infrared pulses to gauge their credibility.

How to use lie detector tests in the workplace

Employers are allowed to use lie detector tests in the workplace, but this must always be optional – the employee has to agree to it – and it must always be used as part of an investigation with fair procedure. Lie detector tests should therefore never be relied on as the sole source of evidence on which to base any allegations.

Similarly, they should only be used if there is reasonable ground for assuming that an employee was acting with gross misconduct.

If you were worried about the honesty of employees, you could include a lie detector test clause in their contract. By signing this, employees consent that, should there be a need for it, they will take a lie detector test.

Can lie detector tests be used as evidence?

At present in the UK, there is no regulation for whether or not employers can use lie detector tests. Lie detector tests will usually be used prior to reaching either a court or an employee tribunal – as such, there are few reported cases where lie detector tests have been used.

However, in UK civil courts, the evidence from a lie detector test can be used in court and tribunal if it’s considered admissible by the judge. If the employee has consented to taking the test in the first instance, it would be unusual for any judge to object to its admission as evidence.

That said, it’s unlikely that the evidence from lie detector tests would be exclusively relied upon as evidence of employee indiscretion. A full investigative procedure would need to be carried out in order to ascertain this, with the submission of alternative corroborating evidence.

It’s also worth being aware that if an employee refuses to take the test, this is not evidence of their guilt. Declining to take one can, however, be used as part of a case against an individual in tangent with supplementary evidence of their indiscretion.

Contact us with your questions

If you have questions about whether or not to use a lie detector test with one of your employees, contact the team at M19 Solutions today. As Manchester’s private investigation specialists, we pride ourselves on our discretion and the affordable cost of our lie detector tests – we’ll help you get to the bottom of things swiftly.