organisation, aid and comfort. Dr Joyce argues that female-only spaces which are open to men, which on her definition includes transgender women, are no longer female-only. Joyce is strongly ideologically committed to the idea that transgender women do not exist, and that language should not be used, a stance that permeates her report. She is entitled to her opinion, but it is of no assistance to the respondents' case, or to this Court.
(ii) Lay evidence
148 Relying on the exception to the opinion rule for lay opinions, the respondents tendered 14 affidavits in support of their argument that the Giggle App was a special measure to promote equality within the meaning of s 7D. While the legitimacy of the application of this exception to the opinion rule may be doubted, I allowed these affidavits to be read in their entirety. None of the witnesses who made those affidavits provided oral evidence at the hearing. The affidavits broadly pertained to the importance of female-only spaces. Most of these witnesses made clear that, by "female-only spaces" they meant female-sex-from-birth-only spaces. Most, but not all, of the witnesses had been users of the Giggle App. Many of the affidavits related to different kinds of women's spaces that were not strictly relevant to the Giggle App. Given my rejection of the respondents' attempt to rely on s 5 and s 7D, turning on the construction of both provisions, it was not necessary to consider further any of these affidavits.
PART 5: CONSTITUTIONAL ISSUES
149 Having found that Ms Tickle's claim of indirect discrimination is made out, I turn to the respondents' two challenges to the constitutional validity of the provisions relied upon for Ms Tickle's case.
(a) Is s 22 beyond the scope of Commonwealth legislative power to the extent it prohibits discrimination on the ground of gender identity?
150 By their amended s 78B notice, the respondents raise two constitutional questions, the first being whether:
s 5B of the Sex Discrimination Act 1984 (Cth) (SDA) is beyond the legislative power of the Commonwealth and ultra vires
The respondents submit the answer is "yes". The Commissioner defends the validity of s 5B and thereby the references to gender identity discrimination in s 22. Ms Tickle adopts the Commissioner's submissions without adding anything of substance to the argument.
