Watch Mark Zuckerberg deliver a speech on free expression at Georgetown University

Facebook CEO Mark Zuckerberg is back in Washington, D.C., today for a speech at Georgetown University on free expression. A Q&A will follow the speech.

This is his second trip to D.C. in a month and comes one week before he is expected to testify before the House Financial Services Committee on October 23 regarding Facebook's impact on the financial services and housing sectors.

Zuckerberg is also slated to appear on Fox News on Friday, where he's expected to address mounting criticism of Facebook's policy to allow misleading political ads.

See also: Mark Zuckerberg says he thought about banning political ads from Facebook, but decided not to