Michael Cohen testifies in Donald Trump's hush money trial. Andrew Weissmann, Adam Klasfeld, and Lisa Rubin join Lawrence O'Donnell.

President Biden and Donald Trump agree to debate in June and September. Also, Maryland Democrats back Angela Alsobrooks in the Senate race. Plus, Sen. Jon Tester vies for a fourth term in Montana. And Luke Russert discusses his book, "Look For Me There: Grieving My Father, Finding Myself." Andrew Weissmann, Simon Rosenberg, Angela Alsobrooks, and Sen. Jon Tester also join Lawrence O'Donnell.