We are often asked by employers to advise on disability discrimination.

Equality Act 2010 states 'a person has a disability if he has a physical or mental impairment which has a substantial and long term adverse effect on his ability to carry out normal day to day activities'. Long term means the impairment has lasted, or is likely to last:

• at least 12 months
• or for the rest of a person's life
• or, if it is in remission, is likely to recur

The guidance on matters to be considered (issued by the Secretary of State, which Tribunals are obliged to have regard to), confirms that impairment can consist simply of the effects of an illness rather than the illness itself. Because of this it is important not to be too rigid when considering an underlying defect in the mind and/or body, and the effects of that.

For example, someone may suffer from liver disease as a result of alcohol dependency. The liver disease (the effect) may amount to a disability but the addiction to alcohol (the cause) would not.

This was the issue that was addressed in the recent case of Walker(W) v Sita Information Networking Computing Ltd. W suffered from a variety of symptoms, which caused significant difficulty in his day to day life. He was clinically obese. The question considered by the Employment Appeal Tribunal (EAT) was whether obesity in itself is a disability.

An occupational health specialist examined W and found there was no actual mental or physical impairment to explain the symptoms which included knee, bowel and stomach problems, anxiety and chronic fatigue. The original Employment Tribunal had focussed, incorrectly, on these findings and concluded there was no disability. However the ET failed to have proper regard for the guidance in terms of looking also at the effects of W's illness.

On appeal to the EAT, the Judge concluded that obesity may not render a person disabled of itself, but may make it more likely that someone is disabled. In W's case the underlying cause of the impairments was the obesity. Although there was no recognised physical or mental cause for these as such, the Judge concluded that W was disabled for the purposes of the Act because of the effect of the impairments. Weighing over 21 stones, the obesity accentuated the problems.