Women's campaigners have questioned a survey by the City of London on transgender rights after nearly half the respondents were excluded from the results.
A report by the corporation said around 70% of 'valid' responses agreed with the general principles that people should be accepted in their 'stated gender identity'.
This would mean people could use toilets, changing rooms and other facilities in line with their self-identified gender at many sites throughout the capital including the Tower of London, Hampstead Heath, the London Museum, the Barbican and many libraries, markets and parks.
Campaigners against the policy are concerned, however, that some men might take advantage of the new freedom and put women and girls at risk.
The trade union-based group Woman's Place dismissed the survey as a sham. It said disregarding so many responses showed it held the views of women in contempt.
The report said nearly 40,000 people had answered the survey between July and September last year to help the corporation develop a 'gender identity policy' in line with the Equality Act.
But 18,459 were discounted because respondents 'primarily answered the introduction About You section which sought to identify the respondent's stakeholder status'.
It is thought most of the responses deemed invalid were by people who did not accept the phrasing of questions which conflated 'sex' and 'gender'.
A spokesperson from the City of London Corporation told LocalGov: 'A number of people who accessed the survey did not answer any of the questions about the gender identity policy proposals. Therefore, these could not be analysed.
'We were pleased with the enormous response to our survey and we thank the over 21,000 people who did answer these questions.
'We took all opinions into account and no one was excluded on the basis of the views they expressed.'
However, Kiri Tunks, co-founder of Woman's Place UK said: 'The City of London Corporation have failed in their obligations under the Public Sector Equality Duty to consider the implications of this policy change on women and to foster good relations between groups with different protected characteristics.
'The fact they disregarded nearly 19,000 responses shows they hold women in contempt and that their consultation was a sham.
'Women have every right to access single sex spaces and we fully expect this decision to be challenged.'