s 23 Comparison by reference to circumstances
(1) On a comparison of cases for the purposes of section 13, 14, 19 or 19A there must be no material difference between the circumstances relating to each case. (2) The circumstances relating to a case include a person's abilities if— (a) on a comparison for the purposes of section 13, the protected characteristic is disability; (b) on a comparison for the purposes of section 14, one of the protected characteristics in the combination is disability. (3) If the protected characteristic is sexual orientation, the fact that one person (whether or not the person referred to as B) is a civil partner while another is married ... is not a material difference between the circumstances relating to each case. (4) If the protected characteristic is sexual orientation, the fact that one person (whether or not the person referred to as B) is married to , or the civil partner of, a person of the same sex while another is married to , or the civil partner of, a person of the opposite sex is not a material difference between the circumstances relating to each case.