Ethics Committee confirms investigation of Tennessee lawmaker

FILE- In this Jan. 4, 2006, file photo, U.S. Rep. John "Jimmy" Duncan, R-Tenn., addresses a business development news conference in Knoxville, Tenn. Duncan said Monday, July 31, 2017, that he will not run for re-election next year because he wants to spend more time with his family. (AP Photo/Wade Payne, File)

WASHINGTON (AP) - The House Ethics Committee is confirming that it's investigating Republican Rep. John Duncan of Tennessee, who is serving his 16th term in the House and has previously announced he won't seek re-election.

The committee's announcement on Tuesday that it has decided to extend its review is the first public acknowledgement of the investigation. The review was prompted by a referral from the nonpartisan Office of Congressional Ethics.

The Ethics Committee didn't say why it's investigating Duncan. But Duncan came under fire in early July after a Knoxville website reported that he paid his son $300,000 for campaign work in the years after the younger man pleaded guilty to misconduct in office.

Also known as "Jimmy," the congressman is a lawyer who served as a state trial judge before entering Congress.