In the wake of the Cambridge Analytica controversy, Facebook indicated that CEO Mark Zuckerberg will testify before Congress. Three congressional committees, including the Senate Judiciary Committee, invited Zuckerberg to testify on April 12. After weeks of pressure, he finally agreed to testify about Facebook’s data-privacy scandal. However, Zuckerberg refuses to appear before members of Parliament in the U.K.

Zuckerberg’s testimony will shed light on Facebook’s role with Cambridge Analytica, a political consultation firm. It was created when Steve Bannon, former White House Chief Strategist, and former Executive Chairman of Breitbart news, approached conservative megadonors Rebekah and Robert Mercer to start a political consulting firm. The firm was hired by the Trump campaign during the 2016 elections. The political consulting firm had access to over 50 million Facebook user’s data, and It wasn’t until former Cambridge Analytica employee Christopher Wylie testified that we learned how Cambridge Analytica gathered this information.

The information was gathered by Aleksandr Kogan, a Russian American who worked at the University of Cambridge. Through the use of a Facebook app that was a quiz for Facebook users to take, it collected the data from those who participated. Additionally, the quiz exposed a loophole in the application programming interface that allowed data to be gleaned from the friends list of the user taking the quiz. Cambridge Analytica sold the data, despite Facebook’s rules against selling data.

What makes this Facebook’s issue is how it betrayed its users’ right to privacy. Facebook allowed a third-party developer to make an app that was purely designed to gather data from the user. All of this was done without the knowledge of any of the quiz takers. Apparently, Facebook had knowledge of this for the past two years and are only now acknowledging that any mistakes were made.

Following this, members of the Senate Judiciary Committee, the House Energy and Commerce Committee and multiple other lawmakers sent letters to Zuckerberg to take accountability. While the Senate heard from other social media representatives how they are protecting user information, lawmakers want to hear from Zuckerberg personally about his knowledge about Cambridge Analytica and its practices in relation to Facebook.

The story is different in London. Members of Parliament are stunned that Zuckerberg refuses to appear before them. Instead, he appointed Facebook’s chief product officer Chris Cox to appear before Parliament and provide evidence on his behalf.

“Mr. Zuckerberg will decide for himself whether he wants to come before the committee, but what I hope is that Facebook will recognize why this is is so significant for people and why it is that people are so concerned about it,” May said, “and ensure that the committee is able to get the answers that they want.”

Zuckerberg expressed regret over the situation, as he took out full page advertisements in U.K. and U.S. newspapers saying, “This was a breach of trust, and I am sorry.”

The scary part isn’t the fact that user data was so easily obtained; it isnt like our online data is so easily read or taken. We willingly allow these companies access to our location, conversations and personal preferences by agreeing to their terms when we sign up for social media. Its the fact that the company decided to withhold their knowledge of the situation, while still taking their time to acknowledge their mistakes even after Cambridge Analytica was found to have sold the data.

The only reasons I could come up with are the leaders at Facebook didn’t want to admit their mistakes to hide their shame, or there is something more foul afoot, involving the personal data of millions of social media users.