(CNN) -- The South Carolina Ethics Commission has charged Gov. Mark Sanford with 37 counts of violating state ethics laws, according to a complaint released by the commission on Monday.
The complaint follows a three-month investigation into Sanford's use of taxpayer money.
Sanford is accused of using tax money to buy business-class airfare on domestic and international flights, flying on a state-owned aircraft to political gatherings or events "which involved no official business," and spending campaign funds for personal use such as buying a ticket to attend President Obama's inauguration in January.
South Carolina law requires state officials to buy the lowest fares available for flights, and bars the use of state aircraft for personal use.
Sanford's office did not respond to requests for comment about the charges.
The governor, once a rising star in the Republican Party before he revealed an extramarital affair in June, faces a hearing along with his legal team before a three-member ethics panel. Cathy Hazelwood, general counsel to the state Ethics Commission, said no date has been set for the hearing.
After arguments are presented, the panel will determine if Sanford broke any state laws. The ethics case involves civil charges that are punishable by fines, and Sanford can appeal decisions up to the state Supreme Court.
Only the state attorney general, Henry McMaster, can decide to pursue criminal charges against the governor. McMaster is reviewing the allegations to determine if any laws were broken.
The new charges compound Sanford's political problems, which have been simmering for months as investigators scrutinized his finances.
State legislators already have filed an impeachment resolution against the governor for leaving the state this summer to visit his Argentine mistress without installing a proper chain of command or informing his staff. A special House subcommittee will meet in Columbia on Tuesday to formally consider the resolution for the first time.
State Rep. Greg Delleney, a Republican and one of the sponsors of the impeachment resolution, said he expects the subcommittee to look over the ethics commission results during the Thanksgiving holiday and decide whether to adjust the measure to include material from the ethics complaint.
Delleney said he thinks Monday's report will give new momentum to the impeachment push.
"The sheer volume of the violations might be useful in bringing some more representatives over to the side of impeachment," Delleney said.
If the special subcommittee decides to move forward with impeachment, the resolution will be passed onto the Judiciary Committee, which will then vote on whether to bring it to the floor of the legislature when lawmakers return to the state capital of Columbia in January.