An undercover investigation by Channel 4 News (UK) reveals how Cambridge Analytica secretly campaigns in elections across the world. Bosses were filmed talking about using bribes, ex-spies, fake IDs and sex workers.
Watch the 19-minute video below: Cambridge Analytica Uncovered: Secret filming reveals election tricks:
What you need to know about Facebook's data debacle
What happens to the data you post on Facebook? And who's responsible for how those personal details are used?
Facebook is under intense pressure to answer these questions — and more — after it admitted that a company linked to President Donald Trump's campaign had accessed and improperly stored a huge trove of its user data.
The controversy erupted as UK media and The New York Times reported that data analysis firm Cambridge Analytica tried to influence how Americans voted using information gleaned from millions of Facebook profiles.