Later this month, the United States Justice Department will offer its closing argument in its antitrust case against Google’s advertising technology business. I have a personal interest in this case because I used to be an advertiser. As a marketing executive in the 1990s and into the 2010s, I leveraged changes in consumer behavior to exploit the precision and cost efficiency of digital advertising. But I left my career in marketing after it became clear that digital advertising capabilities were not only oversold but also causing harm by eroding people’s privacy, compounding challenges for publishers, and facilitating the amplification of harmful content. The DOJ’s case exemplifies how significant Google’s role was in creating and sustaining those harms.

I hope that by sharing how this unfolded, I can help convey why everyone – not just advertisers and publishers – has a personal interest in this case.