Constructive Knowledge: When should an employer know that an employee is disabled?

Constructive Knowledge: When should an employer know that an employee is disabled?


Often cases of disability discrimination are won or lost on the question of whether the employer knew, or ought reasonably to have known, that the individual alleging disability discrimination was disabled for the purposes of the Equality Act 2010 at the relevant time.

Actual knowledge of a disability is usually easier to establish than constructive knowledge but the bar for the employer to be attributed with knowledge of disability (actual or constructive) is generally quite low. 

The recent case of A Ltd v Z is therefore interesting as the Employment Appeal Tribunal (“EAT”) held in this case that an employer could not be said to have constructive knowledge of an employee’s disability in circumstances where the employer was in possession of information which suggested the employee was suffering from mental health issues and had been hospitalised for this reason.

This might usually be enough for an employer to be attributed with constructive knowledge of disability. However, this was a case where the employee concerned had gone to great lengths to conceal her mental health problems. Based on this extreme concealment, the EAT found that the employer could not be held to have constructive knowledge of the employee’s disability.  


Z was employed by A Ltd as a part time finance co-ordinator between February 2016 and 8 April 2017.  

Before Z’s employment with A Ltd started, they had asked her at interview to explain why she had 30.5 days sickness absence recorded in the last year of her previous employment. Z told A Ltd that these absences were due to knee surgery and back and neck injuries suffered as a result of a car accident. Z also completed a form provided by A Ltd in which she confirmed she did not have any physical or mental impairments and that she did not have a disability requiring reasonable adjustments to be made.

During her 14 months of employment, Z was absent for 85 days. Of these 85 days, 52 days were recorded as sick leave, which the Claimant attributed to physical ailments. She made no mention of any mental health conditions (which was the real reason for her absence).  

On 12 February 2017 Z was signed off work for a period of 3 weeks with “low mood”. She told her employer that she was having problems with her son and was feeling “incredibly depressed”. She did not, however, mention any mental health conditions and instead referred to various physical ailments. Her employer was, however, provided with a copy of the GP certificate citing her low mood.

On 1 March 2017 Z was hospitalised for psychiatric care but she did not tell her employer. She again referred to various physical ailments as the reason for her absence. The Respondent was, however, provided with a copy of the hospital certificate stating that Z was to be an in-patient for 4 weeks.

On 27 March 2017 Z was signed off from work for a further period of 3 weeks for “mental health and joint issues” and the employer was provided with a GP certificate verifying this.

Matters came to a head when Z returned to work on 8 April 2017. The Chief Executive informed her that she could no longer be relied upon, given her absences and poor timekeeping, and that as a result it has been decided to dismiss her.  

Z brought a claim against Z for discrimination arising from disability.


It was accepted that Z was disabled for the purposes of the Equality Act 2010. She provided medical evidence which showed she had a long history of mental and psychiatric impairments, namely stress, depression, low mood and schizophrenia.

A Ltd was not, however, held to have actual knowledge of her disability. The case therefore turned on whether her employer could be said to have constructive knowledge of her disability.

The Employment Tribunal (“ET”) found that A Ltd did have constructive knowledge of Z’s disability but, on appeal, the EAT, overturned this finding.

The ET’s decision was based on the fact that by the time of Z’s dismissal, A Ltd was in possession of two GP’s certificate and a hospital certificate indicting a significant deterioration in Z’s mental state. The ET held this made it incumbent on A Ltd to make further enquiries into Z’s mental wellbeing and that their failure to do so prevented them from denying that they ought to have known that Z was disabled.

The EAT however said this was the wrong approach. The EAT agreed that A Ltd should have made further enquiries into the Z’s mental health but the ET should have taken into account what the employer might have found out if they had made those enquires. In this regard the ET had found on another issue that:

  • Z would have continued to suppress information about her mental health problems;
  • she would have insisted that she was able to work normally; and
  • she would not have entertained any proposal for an occupational health referral or any other medical examination which might have exposed her psychiatric history.

The EAT held, therefore, that even if A Ltd could reasonably have been expected to do more to find out about Z’s mental health, it could not reasonably have been expected to know about Z’s disability because Z would have continued to conceal her mental and physiatrist impairments.

The EAT therefore upheld the Respondent’s appeal and the Claimant’s claim for disability related discrimination was dismissed.


The outcome of this case clearly rests on the fact that the Claimant had gone to extreme lengths to conceal her mental health issues from her employer. It is unlikely that the employer would have escaped liability had the Claimant not deliberately concealed the true state of her mental health.

The EAT was clear that the Respondent, armed with the information it had, should have done more to enquire into her mental wellbeing. In normal circumstances (absent the concealment factor) if an employer failed to make further enquires, when they had this type of information in their possession, a Tribunal would be likely to find that the employer should have known about the employee’s disability.

Employers should, therefore, continue to adopt a cautious approach where there are any factors which suggest an employee might be disabled as, ordinarily, failure to make enquires might be fatal to any defence to disability discrimination claim.

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