Are Members Allowed to Use Campaign Funds for Legal Fees?

Q: As the treasurer of the campaign committee of a current House Member, I oversee all of the campaign’s finances. One of the recurring issues I face is distinguishing between campaign expenses, for which we may use campaign funds, and the Member’s personal expenses, for which we may not. I heard recently that Sen. David Vitter (R-La.) has sought permission from the Federal Election Commission to use campaign funds for legal fees related to the “D.C. Madam” legal proceedings. I presume that the FEC will refuse Vitter’s request, as these appear to be personal expenses. Or, are we permitted to use campaign funds for Members’ legal fees?