【Watch Where Sleeping Dogs Lie Online】

On Tuesday,Watch Where Sleeping Dogs Lie Online Mark Zuckerberg will speak with Members of the European Parliament (MEPs) about Facebook data abuses perpetrated by Cambridge Analytica, and how that scandal affected European citizens and government.

It is the second time the Facebook CEO will have to publicly answer for the unintended political consequences of his company's sweeping data collection. In April, Zuckerberg testified before both houses of the United States Congress. During those hearings, he got hammered by some congresspeople about the shadier aspects of data collection. But Team Facebook mostly came out on top thanks to U.S. lawmakers' shaky understanding of how the internet works.

But in technologically and privacy-progressive Europe, the hearings may actually force Zuckerberg to answer some tough questions. Here are three things to watch out for during Zuckerberg's European parliamentary hearing.

1) Data privacy

Cambridge Analytica's use of Facebook data affected 2.7 million Europeans. That's a fraction of the 87 million total Facebook users affected — most of them based in the U.S. But whistleblower Christopher Wylie revealed that Cambridge Analytica used Facebook data and ad-targeting to influence the Brexit campaign.

Facebook is currently rolling out new election advertising policies, and is giving users more control over data collection with its “clear history” feature. But these are all fixes for the future, and don't exactly make amends for how Facebook enabled mass data collection and electioneering. Will the MEPs require that Zuckerberg actually answer for Facebook's role in, say, the United Kingdom leaving the European Union?

2) GDPR compliance

The deadline for compliance with Europe's new online privacy regulations, GDPR, is just three days away. Facebook plans to comply with the regulations. At the same time, it has specifically taken steps to limit the privacy controls required by GDPR for non-EU citizens.

Zuckerberg may (and should) have to answer for how separated European profiles will be from the rest of Facebook; that is, how secure and dedicated to privacy can Facebook really be if only some users receive access to these stringent privacy controls?

Lawmakers may want to ask, if Mark Zuckerberg says Facebook is dedicated to user privacy, why not extend the new tools it's building in for European citizens to everyone? Answering these questions may be important to determining whether Facebook is an actual ally in user privacy and data collection, or whether it is just paying lip service to it.

3) Human after all?

Is Mark Zuckerberg a cyborg/lizard person? The world will be watching his (non) reactions and (generally colorless) pallor to find out.

Here's how to watch the hearings. The fun starts at 12:15 ET.