Texas Local Government Code - LOC GOV'T § 281.078. Bonds as Investments; Security

(a) Bonds issued by an authority are legal and authorized investments for a bank, a trust company, a savings and loan association, an insurance company, a fiduciary, or a trustee and for interest or sinking funds or other public funds of the state or of an agency, subdivision, or instrumentality of the state, including a county, municipality, school district, or other district, public agency, or body politic.

(b) Bonds issued by an authority may be security for deposits of public funds of the state or of an agency, subdivision, or instrumentality of the state, including a county, municipality, school district, or other district, public agency, or body politic, to the extent of the market value of the bonds and appurtenant unmatured interest coupons.