8 USC 1624 - Authority of States and political subdivisions of States to limit assistance to aliens and to distinguish among classes of aliens in providing general cash public assistance

(a) In general 
Subject to subsection (b) of this section and notwithstanding any other provision of law, a State or political subdivision of a State is authorized to prohibit or otherwise limit or restrict the eligibility of aliens or classes of aliens for programs of general cash public assistance furnished under the law of the State or a political subdivision of a State.
(b) Limitation 
The authority provided for under subsection (a) of this section may be exercised only to the extent that any prohibitions, limitations, or restrictions imposed by a State or political subdivision of a State are not more restrictive than the prohibitions, limitations, or restrictions imposed under comparable Federal programs. For purposes of this section, attribution to an alien of a sponsors income and resources (as described in section 1631 of this title) for purposes of determining eligibility for, and the amount of, benefits shall be considered less restrictive than a prohibition of eligibility for such benefits.