To read a counterpoint, click here.

When CBC decided not to air the documentary Transgender Kids: Who Knows Best?, multiple commentators saw it as an affront to empiricism and free debate. Transgender Kids is a BBC documentary that challenges the "gender affirmative" approach to supporting children with gender dysphoria — that is, children whose gender identity does not align with that assigned at birth.

Critics of CBC's decision saw the network as yielding to trans activists, who they saw as rejecting science and acting as an unreasonable mob.

I, however, rejoiced at this decision. Empirical evidence is important. It's often an essential tool when advocating urgent change. But showing this documentary would not have contributed to healthy public debate based on the available scientific evidence.

Presenting facts fairly

In defence of airing Transgender Kids, people have argued that we should present the facts and let people make up their own minds. While I generally agree, important presuppositions are required.

Firstly, the facts must be presented in a fair manner and be presented in their totality. Cherry-picking facts — which this documentary does, as I will describe in detail below — does not make for healthy public debate. Secondly, viewers must generally be rational decision-makers who are capable of critically assessing the ideas being presented. Neither presupposition is accurate in this context.

The documentary centres on Dr. Kenneth Zucker, a psychologist "whose controversial approach with transgender children led to his being sacked in 2015 from a Toronto gender identity clinic," according to The Guardian. His approach to therapy — which includes exploring what he calls the mental health and psychological reasons for gender dysphoria, and not necessarily believing a child who says he or she was assigned the wrong gender — has been described as "disturbingly close to reparative therapy for homosexuals" by Dr. Simon D. Pickstone-Taylor in a letter to the editor published by the Journal of the American Academy of Child & Adolescent Psychiatry. Zucker has strongly denied he has performed reparative or conversion therapy.

Zucker was fired from the Centre for Addiction and Mental Health in 2015. (Jim Ross/New York Times)

Nevertheless, when the documentary was shown in the United Kingdom, 13 mental health and advocacy groups including the UK Council for Psychotherapy, the Royal College of GPs, and the British Psychoanalytic Council and the British Association of Counselling and Psychotherapy condemned the documentary and disavowed the approach put forward by Zucker.

The documentary mentions, for example, that most trans children grow up to be cisgender — that is, not trans: their gender identity matches their sex assigned at birth — citing a figure around 80 per cent. However, past publications on the matter that have influenced that figure have been riddled with methodological issues, such as presuming that children who did not come back for follow-up interviews had desisted from their trans identity.

At the 2014 symposium of the World Professional Association for Transgender Health (WPATH), Dr. Kelley Winters also pointed out that the intake criteria for those studies included many children who were merely gender non-conforming, but not transgender. Most gender non-conforming people, whether children or adults, are not trans. This is the sort of context that is absent in Transgender Kids.

Also absent were details like this: in a 2010 study of 70 adolescents who were given puberty-suppressing hormones, researchers de Vries, Steensma, Doreleijers and Cohen-Kettenis found that not one discontinued treatment in favour of identifying with the gender they were assigned at birth. Practitioners generally report that trans children overwhelmingly grow up into trans adults.

It is unreasonable to expect viewers to know that the empirical data that guides the documentary is flawed. After all, they come to the documentary to learn about a reality with which they are not necessarily well acquainted. Do we really expect them to go search for the publications that underpin each statement and then conduct a careful comparative analysis of its methodological quality versus that of more recent research?

What's more, if you asked people around you whether trans people are normal, I suspect that most would answer "no." Being trans is seen by many to be a suboptimal outcome that should be avoided except in the clearest of cases. In a recent CROP survey prepared for the anti-bullying organization Fondation Jasmin Roy, only 39 per cent of people expressed being very close to believing that gender identity can differ from gender assigned at birth. Everyone else believed to some extent that gender is biologically determined.

Accounting for viewer bias

Given that transitude — the fact of being trans — is understood to be abnormal and undesirable by large swaths of the general population, we cannot expect viewers of the documentary to be unbiased in their assessment of the evidence presented. It is well known that people tend to favour information that confirms pre-existing beliefs. Even if data is presented in an unbiased way, viewers introduce their own bias by overvaluing data that confirms their pre-existing beliefs about gender being based in birth assignment.

In this light, the decision by CBC not to air the documentary should not be seen as an affront to science and public debate. On the contrary: it demonstrates a nuanced understanding of the interactions between empiricism and free debate.

Let's not forget that the stakes are high, considering the vulnerable state of trans people in our society. People are already hesitant to affirm their children's gender identities. Showing the documentary would have been negligent and inimical to healthy public debate.

This column is part of CBC's Opinion section. For more information about this section, please read this editor's blog and our FAQ.