In agreeing to a two-day marathon of testimony before the House and Senate earlier this month, Mark Zuckerberg set a new standard for the political accountability of Silicon Valley’s tech giants: If a company allows a massive breach in its users’ privacy, or the widespread violation of other important rights, the company’s leaders must explain themselves to Congress. If that’s the case, Google CEO Sundar Pichai and YouTube CEO Susan Wojcicki should book plane tickets to Washington at the earliest opportunity.

Late last week, CNN revealed that ads from over 300 companies “ran on YouTube channels promoting white nationalists, Nazis, pedophilia, conspiracy theories and North Korean propaganda.” Facebook, Amazon, and even the U.S. government supplied ads, without knowing exactly where the ads would appear. And because Google, which owns YouTube, allows content producers to monetize their videos, these extremist channels profited from hate and abuse.

Google has been struggling to keep advertisers away from hate speech for years. But because so much of the advertising is programmatic—automatically placed based on an algorithm—these problems keep cropping up. And since advertisers haven’t stopped advertising on YouTube, Google hasn’t faced any real consequences from the scandal.

But in a potentially bigger YouTube scandal, child advocacy groups alleged in a complaint to the Federal Trade Commission earlier this month that the site collects data on children under 13, in violation of the Child Online Privacy Protection Act (COPPA). After collecting this data, YouTube targets users with videos that sometimes feature violent or sexual themes. Some of the content appeared on YouTube Kids, a mobile app directly marketed to children.

Any data collection on children under 13, if true, would trigger large fines for Google. But the company has escaped scrutiny amid Facebook’s Cambridge Analytica scandal and the Zuckerberg hearings. YouTube’s abuses aren’t as directly related to Trump and the 2016 election, but they are just as indicative of the problems of mass data surveillance from ubiquitous digital platforms. The same questions being asked of Zuckerberg—whether his company is a monopoly that’s sacrificing privacy for profits—could be asked of Google’s top brass.