Legal expert Alan Delaney assess when and how employers can use surveillance to investigate false sickness absences

When an employee signed off as unfit for work is rumoured to be in good health and enjoying their time off, the temptation is to rush in with an investigation so the worker 'pulling a sickie' can be punished. However, such revelations put employers in a tricky position; HR managers should think carefully before calling for covert surveillance.

The legal risk in this scenario is that the employment relationship is based on mutual trust and confidence; blazing down a path of covert surveillance, without reasonable and proper cause, is highly likely to undermine that trust and could trigger a constructive dismissal claim.

Often, such issues arise from disgruntled work colleagues telling tales of what they have seen supposedly sick employees doing. In today’s world, this is sometimes accompanied by screenshots from Facebook, showing the signed off employee enjoying life perhaps a little too much. 

At this point it is worth asking if there really is evidence of a clear discrepancy between the employee's ill-health and what they have been observed doing – being signed off work for stress or anxiety does not prevent an employee from looking to enjoy their social life and activities. It will usually be very difficult for employers to second guess what they have been advised in medical fit notes and occupational health reports.


Assuming that there is some evidence of wrongdoing and management decides to look into the matter further, the Employment Practices Code issued by the Information Commissioner's Office (ICO) provides guidance based on the need to comply with data protection law. It states that covert monitoring will rarely be justified and should be undertaken only in exceptional circumstances, such as where criminal activities or equivalent malpractice are suspected.

The code says any surveillance should be strictly targeted, take place within a set timeframe and be carried out under a contract with a private investigator, with legally compliant provisions for the collection and use of information.

Clear rules should be set for access to and disclosure of any information obtained, with any irrelevant material being deleted. And covert surveillance should not take place in areas such as private offices or toilets, unless serious criminal activity is suspected.


The ICO has accepted that covert surveillance can be justified in cases of sick leave being abused. In 2014, Caerphilly County Borough Council signed an undertaking with the ICO after deploying covert surveillance on an employee who had been off for four weeks with stress and anxiety. The ICO accepted that abuse of an employer’s sick pay procedures could amount to malpractice in terms of the code, but that covert surveillance had to be used as a last resort. In the Caerphilly case, however, the commissioner said there were insufficient grounds, as the investigation was launched based on informal comments made to work colleagues.

Where surveillance does provide evidence of wrongdoing, this will usually be admissible before an employment tribunal. In the case of McGowan v Scottish Water, dishonesty was established using covert surveillance, and the resulting dismissal was found by the Employment Appeal Tribunal not to be unfair or in breach of any right to private life.

Nevertheless, employers face both legal and reputational risk if they spy on their staff, and should tread carefully. In all cases it is advisable to carry out a privacy impact assessment to assess whether or not the surveillance is justifiable. This should consider the business aim in question, the impact on the individual being investigated and whether the same objective can be met in a less invasive way.

This exercise is likely to prove useful should there be any subsequent challenge made by an employee, and should help ensure that surveillance is justified and does not backfire on the employer.

Alan Delaney is a director in the employment, pensions and immigrations team at Maclay Murray & Spens