CNN reported Monday that the South Carolina Ethics Commission has charged South Carolina Governor Mark Sanford with breaking 37 state ethics laws.
The charges came after a three-month investigation into Sanford's use of taxpayer money.
The charges state that Sanford used taxpayer money to purchase domestic and international plane tickets. NPR reported that Sanford purchased the tickets to visit his mistress in Argentina and to "political gatherings and events which involved no official business."
Sanford admitted to the affair after he disappeared for five days this summer.
Ethics cases involve civil charges, which are punishable by fines and state legislators have filed an impeachment resolution, which will be considered on Tuesday.
The state attorney general can decide whether to file criminal charges against Sanford.
South Carolina law prohibits the use of state aircraft for private use and mandates that all state officials purchase the lowest fares available.
Sanford's office declined to comment.