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Disability: ‘Physical or mental impairment’

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Last updated 29th March, 2013.

Stammering is a physical or mental impairment. It is less clear which it is (physical or mental), but this does not matter. One case suggests the speech aspects are a ‘physical’ impairment.


Stammering is clearly a ‘physical or mental impairment’.

Is it ‘physical’ or ‘mental’? This does not matter. However, it may be that stammering is ‘physical’ as regards its effect on speech, and ‘mental’ as regards psychological components such as avoiding situations.

(Bear in mind that to be a disability within the Equality Act 2010, the physical or mental impairment must also have a substantial and long-term adverse effect on one’s ability to carry out normal day-to-day activities.)

‘Physical or mental’ impairment

Stammering is clearly an impairment.

Also stammering is a ‘physical or mental’ impairment. ‘Physical or mental’ is not interpreted narrowly to exclude some types of impairment. (The legislative history (below) endorses this wide approach).

B v Servisair (UK) Ltd 2004, Employment Tribunal
A tribunal rejected the employer’s argument that a speech impediment was not a ‘physical or mental impairment’.

‘Physical’ or ‘mental’?

Which is stammering, ‘physical’ or ‘mental’?

The main point is that it does not matter – see below Some guidance and cases. It is not necessary to decide whether it is ‘physical’ or ‘mental’.

If one looks at the causes of stammering, development stammering (stammering which starts in childhood) is neurological. Structural and functional differences have been found in the brains of people who stammer compared with people who do not. There is also genetic evidence. On both brain and genetic research, see The science of stammering (archive of stammering.org), July 2016. This might be seen as either physical or mental.

However, one needs to look at the ‘impairment’ rather than its cause. This may involve looking at the effects of the impairment (again see below Some guidance and cases) It may be that stammering is ‘physical’ as regards its effect on speech, and ‘mental’ as regards psychological components such as avoiding situations (see Hiding the stammer).

B v Servisair (UK) Ltd 2004, Employment Tribunal
A tribunal considered a ‘speech impediment’ to be a physical impairment.
This case considered speech aspects of the stammer, but not psychologial aspects which may be seen as ‘mental’.

The Court of Appeal in McNicol (below) was reluctant to expand on the wording of the legislation (‘physical or mental impairment’), leaving it to the good sense of the tribunal.

Some guidance and cases

A6 It may not always be possible, nor is it necessary, to categorise a condition as either a physical or a mental impairment. The underlying cause of the impairment may be hard to establish. There may be adverse effects which are both physical and mental in nature. Furthermore, effects of a mainly physical nature may stem from an underlying mental impairment, and vice versa.

A7. It is not necessary to consider how an impairment is caused, even if the cause is a consequence of a condition which is excluded. For example, liver disease as a result of alcohol dependency would count as an impairment, although an addiction to alcohol itself is expressly excluded from the scope of the definition of disability in the Act. What it is important to consider is the effect of an impairment, not its cause – provided that it is not an excluded condition. …
2011 guidance, para A6 and A7

Walker v Sita Information (link to bailii.org), 2013 Employment Appeal Tribunal (EAT)
The Claimant suffered from a wide range of symptoms which could not be attributed to a recognisable pathological or mental cause. They were regarded as functional overlay, accentuated by his being obese. The employment tribunal held he did not have a physical or mental impairment. The EAT overturned this. The impairment did not have to be caused by something physical or mental. Plainly in this case the claimant did have a physical or mental impairment. “Chronic fatigue syndrome may mix the two; bowel and stomach problems, and knee problems, are physical; anxiety and depression are mental.”

McNicol v Balfour Beatty Rail Maintenance 2002, Court of Appeal
“It is left to the good sense of the tribunal to make a decision in each case on whether the evidence available establishes that the applicant has a physical or mental impairment with the stated effects. Such a decision can and should be made without substituting for the statutory language a different word or form of words in an ambitious and unnecessary attempt to describe or to define the concept of ‘impairment’.

A bit of legislative history

The legislative history indicates that ‘physical or mental’ is intended to have a wide meaning.

In the Standing Committee Debates considering the Disability Discrimination Act 1995 (Hansard, H.C., Session 1994-95, Standing Committee E, cols 71,72, 101) the then Minister of Social Security and Disabled People, William Hague, made it clear that physical and mental are intended to be seen in their widest sense and should comprehensively cover all forms of impairment.

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