Shapiro was a part of a set of three welfare cases all heard during the 1968–69 term by the Supreme Court, alongside Harrell v. Tobriner and Smith v. Reynolds.

The question posed by Shapiro was whether Congress, in writing Section 602(b) of the Social Security Act, overstepped its regulating powers by giving states the ability to restrict travel.

[6] Vivian M. Thompson moved from the Dorchester neighborhood of Boston, Massachusetts, to Hartford, Connecticut, in June 1966 to live with her mother.

States such as Connecticut that receive federal funding for their welfare programs may have, at a minimum, a one-year residency period via Section 602(b) 42 of the Social Security Act.

[16] The majority opinion, held by Judge Smith in favor of the plaintiff (Thompson), declared that residency waiting periods for welfare via Section 17-2d were unconstitutional under the Equal Protection Clause of the Fourteenth Amendment.

[6] They believed that a one-year residency requirement had no 'permissible purpose' other than to discourage the movement of people who may seek welfare from moving to Connecticut.

Judge Claire acknowledged that a state's regulation of any program might not be well-thought-out, but he argued that it is not the District Court's job to change.

Timeline was created from Jordan Lampo's legal article The Last Days of the Warren Court: How Justice Brennan Orchestrated Shapiro v. Thompson (1969).

Jordan Lampo explained, detailed and listed in chronological order all internal Supreme Court documents related to the Shapiro v. Thompson decision.

In the majority opinion, themes of equal opportunity, mobility through free movement, and liberty were foundational to the reasoning that Justice Brennan employed.

[31] The Court rejected the argument that Congress had the power to authorize residency requirements, as it was a violation of the equal protection clause.

[32] The State of Connecticut argued in every hearing that residency requirements would make planning a budget more predictable, citing administrative justification.

In response, Cox cites "South's Relief Aid Sends Many North" by Peter Kihss,[33] as evidence that states were not reducing their administrative or financial burden in the limitation of welfare.

[36][37] Justice Brennan cited the 'compelling interest' theory as he argued that Shapiro v. Thompson, being an issue of discrimination, allowed a standard of strict scrutiny to be applied.

Justice Warren argued simply that, under its enumerated powers, Congress had the right to authorize States to set residency requirements.

[39] Justice Warren, in his reading of the Constitution, surmised that the Social Security Act represented a form of "cooperative federalism" during the New Deal period, aimed at easing the burden on states.

Justice Warren cites that in 1935, there were welfare residency requirements under the Social Security Act directly set by Congress for the District of Columbia.

To strike down any law, statute, act, or idea that restricts a 'fundamental right' waters down the equal protection clause and the Fourteenth Amendment.

[42] Shapiro v. Thompson, the second successful 'welfare test case'[1] which played a pivotal role in reshaping welfare rights laws, policies, and procedures.

[10][5]: 125–127  As the primary counsel for NWRO and a key member of the LSP through Columbia's Law School, Sparer's intellectual framework guided the litigation of 164 cases before the Supreme Court by 1974.

This concerted effort provided crucial legal support, particularly to poor Americans and mothers, influencing the evolution of welfare policies.

Felicia Kornbluh argues that welfare has since been unable to catch the national attention as it did in 1969, Shapiro v. Thompson was simply a product of its time.

[5] Through the 1970s, three-quarters of the Supreme Court's docket dealt with civil rights and liberty cases, akin to Shapiro v. Thompson.

[47] Furthermore, in Memorial Hospital v. Maricopa County, 415 U.S. 250 (1974), the Supreme Court struck down a one-year residency requirement in Arizona to receive nonemergency medical aid paid for by the state.

[47] California received a waiver from the Secretary of Health and Human Services to sidestep Shapiro v. Thompson, making the residency requirement pseudo-legal.

In its holding, the court stated that the Secretary of HHS had not adequately considered public comment on the issue and invalidated the waiver.