25 U.S.C. § 410: Moneys from lease or sale of trust lands not liable for certain debts

No money accruing from any lease or sale of lands held in trust by the United States for any Indian shall become liable for the payment of any debt of, or claim against, such Indian contracted or arising during such trust period, or, in case of a minor, during his minority, except with the approval and consent of the Secretary of the Interior.