Final answer:
Thurgood Marshall was the NAACP lawyer who argued on behalf of Linda Brown in the landmark Supreme Court case Brown v. Board of Education, which ruled that school segregation was unconstitutional.
Step-by-step explanation:
In 1952, the NAACP lawyer who argued on behalf of Linda Brown, a black girl barred from attending the all-white elementary school in her neighborhood in Topeka, Kansas, was Thurgood Marshall. This case, known as Brown v. Board of Education of Topeka, Kansas, was pivotal in the battle against segregation in American public schools. Marshall's argument before the U.S. Supreme Court was integral in leading to the 1954 landmark decision that declared school segregation unconstitutional, rejecting the 'separate but equal' doctrine established by Plessy v. Ferguson and setting a significant precedent for the Civil Rights Movement. Thurgood Marshall later became the first African-American justice of the Supreme Court, cementing his legacy in the fight for civil rights.