Sen. Mary Landrieu (D-LA) is in a bit of trouble with the law for misusing taxpayer dollars.

Landrieu, who is up for a tough re-election this November, violated federal law when she charged her private jet round-trip flight from New Orleans to Lake Charles where she would be attending a campaign fundraiser to the taxpayers, costing them more than $3,000. Landrieu took the plan ride the day she took her infamous ride on Air Force One, where she accompanied President Obama.

Thanks to investigative work by CNN, Landrieu’s campaign team is calling the federal violation a “mistake” in the billing process. That’s a pretty hefty mistake.

Landrieu spent more than $3,200 in taxpayer money to fly 400 miles round trip from New Orleans to Lake Charles, Louisiana, where she attended a $40-per person fundraising lunch with hundreds of women, according to Senate records and Landrieu campaign information. It is illegal to spend government money campaigning.

Landrieu’s campaign spokesman, Fabien Levy, said in a statement that the charter company mistakenly billed Landrieu’s Senate office instead of her re-election campaign. Levy said the campaign noticed the error a few weeks ago and asked the company to refund the Senate office and bill the campaign, which the company did. Levy said Landrieu’s re-election campaign paid for the flight August 4, almost nine months after the November 8 trip.

“We take our finances very seriously and are glad we caught the vendor’s mistake and were able to rectify the matter as soon as possible,” Levy said.

But the Landrieu campaign did not even notice the supposed billing “mistake” until July 29, 2014 which just so happened to be two days before USA Today reported that Landrieu was one of the most frequent senators charging private jet flights to the taxpayers.

Landrieu cost taxpayers $47,000 for her taxpayer-funded private flights, just in 2013 alone.

And what Landrieu’s campaign team forgets to mention is that Landrieu, though the mistake has been corrected, still violated federal law. Landrieu now faces potential civil fines for misuse of taxpayer dollars.