Census Bill has opened a 'huge Pandora's box around gender identification'published at 10:51 Greenwich Mean Time 20 December 2018
Ms McAlpine says there are a number of feminists that don't believe in self-identification.
Ms Hyslop says we've got to test the questions, they must be credible and people must have confidence in them.
Tory MSP Jamie Greene says this has opened up a "huge Pandora's box around gender identification".
There still is an issue around the 2011 census as the sex question guidance was based on self-identification but was a compulsory binary question, he says.
With a voluntary question on gender identity now being added, will that change the way people answer the mandatory sex question, asks Mr Greene.
Ms Hyslop says this is the critical point and Mr Greene is cutting to the chase as this is a social question, reminding the committee that the religious and language questions were controversial in the past.
She points out the census is only about answering questions for information and is not about status.