25 U.S.C. § 4134

(a) In general Subject to section 4133 of this title and the Indian housing plan for an Indian tribe, the recipient for that tribe shall have— (1) the discretion to use grant amounts for affordable housing activities through equity investments, interest-bearing loans or advances, noninterest-bearing loans or advances, interest subsidies, leveraging of private investments, or any other form of assistance that the Secretary has determined to be consistent with the purposes of this chapter; and (2) the right to establish the terms of assistance. (b) Investments A recipient may invest grant amounts for the purposes of carrying out affordable housing activities in investment securities and other obligations as approved by the Secretary.