Chris Elmendorf, Ann Ravel and Abby Wood in SF Chronicle:
Micro-targeted political advertising raises two sets of concerns:
It’s likely to exacerbate political polarization, and the erosion of broadly shared norms against hateful ideologies such as white supremacy. Political scientists have long thought that candidates refrain from explicitly racist appeals because of the risk of backlash. But if no one but racists will hear a racial campaign appeal, there’s not much incentive to hold back.
Those who would challenge false, hateful or misleading advertisements are rendered mute. They don’t know what’s been said, or to whom, because micro-targeted advertising happens out of public view. It’s only through the efforts of diligent reporters and special counsel Robert Mueller that we have even the foggiest sense of the ads placed and targeted through Internet platform companies such as Facebook. By contrast, in the days when broadcast television was the advertising medium of choice, it was easy for political candidates to learn what their opponents were saying and to buy competing ads that would reach the same audience. Federal law provided a helping hand, requiring local broadcasters to maintain public records of paid political advertising, thus revealing the media markets in which the ads were run.