Photo: Brais G. Rouco/SOPA Images/LightRocket via Getty Images
Aleksandr Kogan, the academic who helped Cambridge Analytica harvest Facebook's user data, is one of three witnesses schedules to testify next week at a Senate Commerce Committee hearing.
Why it matters: This controversy has stretched on for months, and every new hearing or controversy raises the profile of privacy issues on Capitol Hill.
Go deeper: Facebook's year of a thousand cuts