The concept of "discrimination" involves making comparisons - you can't "discriminate" against someone unless you treat them in a way which is different from the way you treat someone else. So a comparator is essential if a claim under the Disability Discrimination Act 1995 is to succeed and the question of how you decide who it is appropriate to compare with is therefore fundamentally important.

The question became a particularly "hot potato" on 25th June 2008. On that date the House of Lords decided (in a non-employment law case) that the criteria laid down by the Court of Appeal in 1999 for selecting the correct comparator were wrong ( London Borough of Lewisham v Malcolm HL 2008 UKHL 43). In Clark v Novacold Ltd CA 1999 the Court of Appeal had held that the wording of what is now DDA 1995 s.3A was ambiguous and that the ambiguity should be resolved essentially in favour of the disabled person. The House of Lords has now ruled, in essence, that that was wrong.

The EAT has subsequently confirmed that what the House of Lords said in London Borough of Lewisham v Malcolm HL 2008 (above) is equally applicable in employment law cases.

The issue of selecting the correct comparator is particularly important when considering whether a disabled person is placed at a disadvantage such as to give rise to a duty on an employer or prospective employer to make "reasonable adjustments" (Disability Discrimination Act 1995 s.4A).

For notes on the Equality Act, in force from 1st October 2010 go to our sister website on the Equality Act 2010 at www.equalityact.co.uk.