Conversation so far:
how did Steven Levitt get involved with the defamation suit
John Lott filed suit for defamation against Steven Levitt and HarperCollins Publishers over the book Freakonomics and against Levitt over a series of emails to retired economist John B. McCall.

Question: What kind of defamation?
Self-contained rewrite: What kind of defamation did John Lott file for against Steven Levitt and HarperCollins Publishers?