Facebook founder and chief executive officer Mark Zuckerberg will strike an apologetic tone when he appears before Congress this week, expressing contrition for the website’s oversight of user data and its role in the 2016 election. In testimony at a joint hearing of the Senate Judiciary and Commerce committees on Tuesday and before a House committee on Wednesday, the famously aloof social media executive will take responsibility for failing to handle its civic duties with more care. “It’s clear now that we didn’t do enough to prevent these tools from being used for harm … That goes for fake news, foreign interference in elections, and hate speech, as well as developers and data privacy,” he will say, according to advance testimony to the House Committee on Energy and Commerce released Monday.