NASHVILLE (AP) - A prominent school voucher advocate in Tennessee paid for a private plane to take public officials including potential Republican and Democratic candidates for governor to North Carolina on a private school tour.

The Tennessean reports (http://tnne.ws/2cYx1In) that the trip organized by Lee Barfield included Republican House Speaker Beth Harwell and former Nashville Mayor Karl Dean, a Democrat. Both are considering bids to succeed term-limited Gov. Bill Haslam in 2018.

State law prohibits lawmakers from receiving major gifts from lobbyists or their employers. Barfield, the brother-in-law of former Republican U.S. Senate Majority Leader Bill Frist, has lobbied for a variety of companies in the past and is on the board of directors for the American Federation for Children, a pro-voucher group, but he was not registered to lobby when the trip took place last year.

"As a citizen, I am permitted to take these officials if they want to go on a fact-finding trip," Barfield told the paper.

The Tennessean in recent days has detailed other expense-paid trips taken by lawmakers, including a 2011 tour organized by GOP donor Andy Miller Jr. for six lawmakers to visit Europe to learn about what he calls the dangers of radical Islam. In 2014, Mark Gill, another voucher advocate, allowed five lawmakers to stay at his seaside condominium in Alabama.

Harwell has said she would prefer lawmakers don't take trip like the ones to Europe or Alabama, but that if they do, they should be disclosed to the public. The trip to North Carolina was focused on learning more about schools, said Harwell spokeswoman Kara Owen.

"This was not recreational in nature - neither the speaker nor the mayor would have participated if it were," she said.

Dean said the trip involved a tour of the private Thales Academy in Raleigh. The group flew there in the morning and re turned in the afternoon.

Dean, who has long been a supporter for more charter schools, said he respects Barfield but that the trip "didn't alter my opinion at the end of the day." Dean said he still opposes school vouchers and charter schools run by for-profit companies.

"For me, it was a day trip where it made sense to see the school. You go, you see them and you come back," Dean said.