Social media harms: Mark Zuckerberg’s evidence-based practice

  • February 6, 2024

At the recent Senate judiciary hearing on “Big Tech and the Online Child Sexual Exploitation Crisis” Meta CEO Mark Zuckerberg said to parents present: “I’m sorry for everything you’ve all gone through, it’s terrible… No one should go through the things that your families have suffered and this is why we invest so much and we are going to continue doing industry-wide efforts to make sure no one has to go through the things your families have had to suffer.” This statement to an unimpressed looking audience was widely, and perhaps rather generously, reported as an apology (“a regretful acknowledgement of an offence or failure”) and it received a great deal of press coverage.

Less heavily reported, but to my mind much more surprising, is something else…

At the start of the hearing, Zuckerberg said, “The existing body of scientific work has not shown a causal link between using social media and young people having worse mental health.  I think it’s important to look at the science, I know people widely talked about this as if that is something that’s already been proven, and I think that the bulk of the scientific evidence does not support that.”

On the face of it this statement is a flat contradiction of much of what has been taken as read in recent public debates about harms from social media. But…Zuckerberg’s remarks are, like his apology, carefully worded. In particular the second of his assertions isn’t wildly out. It is true that the bulk of evidence doesn’t support a causal link because it is cross-sectional and shows only associations. And it is also true that some of the case has been overstated – for example there is little robust evidence that social media “cause” depressive disorders or suicidal thinking in people not already struggling with those problems.

On the other hand, the first assertion seems shakier. It says more definitely that there is no evidence across the whole area of mental health. And yet any reasonable conclusion based upon what we know about how the online world works (some of it reviewed by experts in our recent book on social media and mental health) is that it is likely harms will flow from addictive patterns of social media use, from online bullying and harassment, malicious use of personally-shared photographs, solicited contact by predatory adults and the like.

Unfortunately a “reasonable conclusion based upon what we know about how the online world works“ is not the same as rock-solid proof that is going to stand up against hot shot lawyers from Team Zuckerberg arguing about what “shown a causal link” and “worse mental health” mean.

I can’t help thinking that fulminating about the bad faith of the tech CEOs is about as productive as grumbling about the ignorance and bias of academic peer reviewers. There may be political and legal avenues to follow in pursuit of a safer online world, but for researchers the next step must be to revisit how we undertake studies in a methodologically and logistically challenging area: what exactly is the research we need to do that will produce irrefutable proof that certain sorts of remediable social media experiences are bad for the mental health of those experiencing them? And perhaps as importantly – how can we explain the findings to politicians and legislators?

Allan House

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