Recent reports suggest that since 2010, the number of UK employers conducting workplace drug testing has increased by up to 470%. Drug testing has traditionally been limited to safety critical roles. However, it is becoming more common across a wider variety of sectors (such as retail, professional and financial services). According to the latest Global Drug Survey, within the last 12 months 20% of British respondents have gone to work whilst coming down from drugs. It is hardly surprising then, that businesses are upping the ante.

Under current legislation, employers must have an individual’s consent to test for drugs. Consent provisions are often included in an employer’s contracts of employment or staff handbook. However, an employer can also ask an employee to take a drug test where there is reason to suspect that s/he is acting under the influence. If an employee unreasonably refuses to give their consent in such cases, they may face disciplinary action and possible dismissal for failing to follow a reasonable management instruction and/or gross misconduct.

Companies are under an overriding statutory duty to ensure a safe working environment for their staff. Therefore, if an employer does not deal appropriately with a drug taking employee, affected staff may be able to issue proceedings against them for breach.

But drug testing does not indicate whether an individual’s ability to do their job is affected, nor does it evidence a safe working environment. It simply highlights what substances a person has in their system. The active ingredient in cannabis, for example, can remain detectable days after an individual has smoked it meaning that they could have had a joint on Friday, but test positive at work on Monday, even though their performance may be unaffected at the time of testing.

There is also evidence to suggest that eating poppy seed bread could result in someone testing positive for opiates, but what is an employer to do? The employee’s performance may be completely unaffected but, technically, this person will have failed the test, even though they have not taken any drugs.

The difficulty is that drug use may (or may not) affect an individual’s performance, behaviour or conduct in the workplace in the same way that enjoying a few glasses of wine, experiencing a difficult break-up, partaking in a religious fast (such as Ramadan) or having a baby may do so. In each of these examples, an employee’s productivity and their ability to concentrate may be affected; they may suffer from fatigue or mood swings. Where (and how) does an employer draw the line?

It is becoming increasingly difficult for businesses to navigate this minefield, and the current popularity of “legal highs” is likely to complicate matters. Employers therefore need to take great care, and there are a number of factors which you would be well-advised to consider, before drug testing any employee:

  • Have well-drafted consent provisions in your contracts of employment and staff handbook.
  • Define what you regard as drug abuse. Is it the use of illegal substances? Or the misuse of prescription drugs and medications too? What about the use of “legal highs”?
  • Consider whether to adopt a “zero tolerance” or a “cut-off” approach (whereby an individual with drugs in their system under a certain level will not be disciplined).
  • Have clear policies and procedures in place, which explain when drug testing will be required and the procedure for such testing.
  • Follow these policies and procedures consistently across all levels of your organisation so as to guard against allegations of favouritism, marginalisation or discrimination.
  • Ensure that testing is no more intrusive than necessary to achieve its purpose.
  • Be aware of your obligations under the Data Protection Act regarding the collection and processing of sensitive personal data.
  • Seek appropriate legal advice so as to mitigate the risks of discrimination, assault and/or breach of trust and confidence allegations being levelled against you, as well as claims for constructive unfair dismissal.

This blog first appeared as an article in HR Magazine in October 2014.