Substance misuse in the workplace

Substance misuse in the workplace


Author: Michael Briggs

Applies to: England and Wales

Use of illegal substances and alcohol dependency is prevalent within society and can be an issue which employers need to deal with in the workplace. We consider the possible problems and how to avoid the pitfalls.

An employee's use of illegal drugs whether at work or at home can impact upon the workplace in a variety of ways: affecting relationships with colleagues, increasing absence, reducing productivity and causing an unsafe working environment for themselves and others.

For individuals, the possession of illegal drugs and/or selling/buying of drugs exposes them to the risk of criminal charges. Employers may find it difficult to know what they can or should do where they are faced with an employee with a substance misuse problem.

Employers' legal responsibilities

Health and safety

Employers have a legal duty to ensure, as far as reasonably practicable, the health, safety and welfare of all their employees. This involves providing a safe place (and systems) of work. The requirements for this will depend upon the nature of the employer's business and the particular role of the relevant employee. For example, an employer will be required to put more measures in place to ensure safety where an employee is operating machinery or driving a company vehicle.

Disability discrimination

Although drug addiction is not itself a disability, any physical or mental impairment arising from drug use (for example, depression) may be capable of amounting to a disability under the Equality Act 2010. Where this is the case the obligation on the employer to make reasonable adjustments will apply.

Criminal law

Employers could also be breaking the criminal law if they knowingly allow drug-related activities in the workplace and fail to act. Employers therefore need to ensure they do not "turn a blind eye" to any suspicious behaviour and consider whether police involvement is appropriate.

Drug testing in the workplace

The question often arises whether employers can test their employees for drugs? Drug testing is a highly invasive process so will require employee consent and employers need to proceed with caution.

Where it is proportionate and necessary employers will be able justify testing employees. However, this will depend on the circumstances of each case. Employers will need to consider their business needs for testing carefully rather than impose testing as a knee-jerk reaction to a perceived problem which could be solved in a less invasive way.

Where working under the influence of drugs could give rise to health and safety considerations, for example because staff are driving, or operating heavy machinery, or the employer already has some evidence to suspect that employees are misusing substances, it should be able to show justification for testing.

The Information Commissioner's Office has issued good practice guidance which contains some recommendations in respect of situations where drug testing will or will not be acceptable.

Employers also need to be aware of their obligations under the Data Protection Act 1998 in respect of data generated by any drugs testing. This will be sensitive personal data and subject to more onerous obligations than personal data in the ordinary sense. These include keeping the data securely and not passing it on to third parties without the explicit consent of the relevant employee.

Practical tips for employers

  • By undertaking regular risk assessments and ensuring that any potential issues surrounding substance misuse in the workplace are addressed, employers can go some way to show that they are providing a safe place of workTraining should be given to staff, particularly those in managerial and supervisory roles about the nature and causes of drug problems and the effect of drug misuse on workplace safety and performance. This will enable warning signs to be identified at an early stage and will ensure that managers know what they should do if they suspect an employee of misusing drugs
  • Have a comprehensive drug and alcohol policy in place which sets out the employer's stance on substance misuse in the workplace. Employees should be encouraged to seek assistance where required and it should be made clear that those who seek help will be treated sympathetically
  • This policy could include drug testing provisions; the drug testing methods to be used and the purpose of testing should be clearly stated. Note that, this will not be appropriate for all environments. If drug testing is assessed to be an important requirement then consider including a contractual obligation to co-operate with such testing in employees' contracts of employment
  • Be aware of changes to the law regarding substance misuse. For example, a recent change made in March 2015 means that it is an offence to drive while over a specified limit relating to drug use. This is similar to the drink driving laws and will mean that police no longer need to show impairment to driving due to drugs, just that the driver is over the limit. Employers should ensure that any drivers who use a vehicle for work purposes are aware of this change to the law, and understand its implications. The offence carries a mandatory disqualification from driving and a maximum of six months' imprisonment
  • In so far as possible, employers should treat drug problems in a similar way to other health issues. Support should therefore be provided to enable the employee to return to his/her duties as soon as possible, which may include referrals to Occupational Health Advisors or other specialist treatment providers
  • Include provisions in the contract of employment and/or disciplinary policy which relate to the misuse of drugs and state exactly what the consequences of a breach of policy or a failed drug test may mean. Disciplinary policies should give examples of behaviours which may be regarded as gross misconduct (and therefore lead to summary dismissal) and these are likely to include using or selling drugs in the workplace. Where drug related issues spill over into the workplace, misconduct may be the most appropriate potentially fair reason for dismissal. Before any dismissal, employers should ensure that there is a fair reason for dismissal and that a fair procedure has been followed
  • Capability/performance related matters should be dealt with in accordance with the appropriate procedures.


This document is for informational purposes only and does not constitute legal advice. It is recommended that specific professional advice is sought before acting on any of the information given.

About the Author

contact photo

Michael Briggs

Senior Associate

0370 086 5066

Michael is an experienced employment lawyer who provides practical, commercial and results-driven advice to a wide range of clients in respect of disciplinary matters, redundancy & reorganisation, absence and performance issues, employment contracts & handbooks and executive appointment & exits. Michael also defends employment tribunal claims.

Share this page