He was charged with ethics violations.

Ethics Committee Drops Last of 84 Charges Against Gingrich

 The House ethics committee dropped the three remaining ethics charges against Speaker Newt Gingrich (R-Ga.) yesterday, despite finding that Gingrich repeatedly violated one rule by using a political consultant to develop the Republican legislative agenda.

 The ethics panel decided to take no further action because there is no evidence that "Rule 45" violations are continuing in the speaker's office, a post Gingrich has held since 1995. Consultant Jeffrey Eisenach's work took place while Gingrich was the GOP minority whip in 1990-91.

 Eisenach was a paid consultant to GOPAC, a Republican political group formerly chaired by Gingrich, according to the letter.

 Gingrich is paying $300,000 for the costs of an ethics committee investigation after admitting last year he made inaccurate statements during a lengthy probe into Democratic allegations that he misused tax-exempt donations. Gingrich denied the charges but submitted to a reprimand by the House.

https://www.washingtonpost.com/wp-srv/politics/govt/leadership/stories/101198.htm