Question: Which Supreme Court case in the 1940s was related to the protest that the participants of the Civil Rights Movement at The Greyhound Bus Station at 210 South Court Street in Montgomery, Alabama participated in?

Context paragraphs:
Lakuarriaga Station: Fifteen years ago, the old bus station of Vitoria-Gasteiz, Spain was demolished.  Then some years later, Artium Museum was built in the place where the old bus station had been built.  After demolishing the old bus station, a new one was built in Los Herran street.  However, the current bus station in Vitoria, the one in Los Herran street, is just working temporarily, because in May 2011 the construction of the new bus station was going to begin.  Some months prior, the town hall organized a competition in which the participants, taking in account some requirements, were asked to design an intermodal bus station in Vitoria.  Eight companies presented their jobs, and the town hall decided that the project designed by Fernando Ruiz de Ocenda, Iñaki Usandizaga and Francisco Javier Garcia de Acilu (in contribution with trakteplan engineries) was the most appropriate.

Cleveland Court Apartments 620–638: The Cleveland Court Apartments 620–638 is a historic apartment building in the Cleveland Court Apartment Complex in Montgomery, Alabama.  It is significant to the history of the modern Civil Rights Movement in the United States.  Unit 634 was home to civil rights activist Rosa Parks, her husband Raymond, and her mother, Leona McCauley, during the Montgomery Bus Boycott from 1955 to 1956.  The building was placed on the Alabama Register of Landmarks and Heritage on March 30, 1989 and the National Register of Historic Places on October 29, 2001.

Greyhound Bus Station (Montgomery, Alabama): The Greyhound Bus Station at 210 South Court Street in Montgomery, Alabama, was the site of a violent attack on participants in the 1961 Freedom Ride during the Civil Rights Movement.  The May 1961 assaults, carried out by a mob of white protesters who confronted the civil rights activists, "shocked the nation and led the Kennedy Administration to side with civil rights protesters for the first time."

Alabama Chapter of the Communist Party USA: The Alabama Chapter of the Communist Party USA (CPUSA) was one of the most influential political bodies organizing poor African-Americans in the South during and after the Great Depression.  Started with just two members, the Alabama chapter CPUSA was established in Birmingham Alabama in 1928, and remained active until it was forced underground by Ku Klux Klan (KKK) and police repression, and was disbanded when it was outlawed in 1951.  During the height of Jim Crow and the Great Depression, the Alabama CPUSA organized some of the poorest African-American communities in the country, and was successful in leading organization drives in multiple industries including the Sharecroppers' Union, mine, mill, and industrial workers, as well as leading numerous campaigns to organize unemployed workers.  The Alabama CPUSA also played a vital role in organizing African-Americans during a period where many activists would later become leaders of the emerging Civil Rights Movement.  Ashbury Howard, who later was a significant leader in Alabama during the Civil Rights Movement, and Rosa Parks, who would later commit an act of civil disobedience launching the Montgomery Bus Boycott, were both trained and active with the Alabama CPUSA.

Greyhound Bus Depot (Columbia, South Carolina): The Greyhound Bus Depot is a former Greyhound Lines intercity bus station in Columbia, South Carolina.  It is at 1200 Blanding Street in downtown Columbia.  The depot was named to the National Register of Historic Places on December 28, 1989.  After the bus terminal was closed, the building became a bank.  Currently, it is a physician's office.

Philadelphia Greyhound Terminal: The Philadelphia Greyhound Terminal is the primary intercity bus station in Philadelphia, Pennsylvania.  It is located at 1001 Filbert Street in Center City Philadelphia, immediately north of The Gallery at Market East shopping mall and the SEPTA Regional Rail Jefferson Station, a few hundred feet east of the Pennsylvania Convention Center and Reading Terminal Market, a few hundred feet south of the Trocadero Theatre and the south edge of Philadelphia's Chinatown district, and within 1/2 mile of Independence Mall, the U.S. Mint, and City Hall.  The station building, which underwent an interior remodeling in early 2007, is relatively small and nondescript, belying its importance as one of the busiest, long distance, bus-only terminals in the United States.  The terminal was the 4th busiest Greyhound bus station in the U.S. in 2013.

Greyhound Bus Terminal (Evansville, Indiana): The Greyhound Bus Terminal in downtown Evansville, Indiana, also known as the Greyhound Bus Station, is a Moderne-style building from 1938.  It was built at a cost of $150,000.  The terminal, located at the corner of Third and Sycamore streets, was listed on the National Register of Historic Places in 1979.

V.L. v. E.L.: V.L. v. E.L., 577 U.S. ___ (2016) , is a case decided by the Supreme Court of the United States concerning the adoption rights of same-sex couples.  In 2007, a Georgia Superior Court granted adoption rights to V.L., the partner of E.L., the woman who gave birth to their three children.  However, after moving back to Alabama, the couple split up.  E.L. tried to block V.L. from seeing the children, but V.L. filed a lawsuit seeking visitation and other parental rights.  On September 18, 2015, the Supreme Court of Alabama ruled that the state did not have to recognize the adoption judgment, saying that the Georgia court misapplied its own state law.  The court voided the recognition of the adoption judgment in Alabama.  V.L. petitioned the United States Supreme Court to stay the ruling during her appeal and allow her to see her children.  On December 14, 2015, the Supreme Court stayed the ruling pending their action on a petition for a writ of certiorari filed by V.L. On March 7, 2016, the Supreme Court of the United States reversed the decision of the Alabama Supreme Court by per curiam summary disposition.

Montgomery bus boycott: The Montgomery bus boycott, a seminal event in the Civil Rights Movement, was a political and social protest campaign against the policy of racial segregation on the public transit system of Montgomery, Alabama.  The campaign lasted from December 5, 1955—the Monday after Rosa Parks, an African American woman, was arrested for refusing to surrender her seat to a white person—to December 20, 1956, when a federal ruling, "Browder v. Gayle", took effect, and led to a United States Supreme Court decision that declared the Alabama and Montgomery laws requiring segregated buses to be unconstitutional.  Many important figures in the Civil Rights Movement took part in the boycott, including Reverend Martin Luther King Jr. and Ralph Abernathy.

Freedom Riders: Freedom Riders were civil rights activists who rode interstate buses into the segregated southern United States, in 1961 and subsequent years, in order to challenge the non-enforcement of the United States Supreme Court decisions "Morgan v. Virginia" (1946) and "Boynton v. Virginia" (1960), which ruled that segregated public buses were unconstitutional.  The Southern states had ignored the rulings and the federal government did nothing to enforce them.  The first Freedom Ride left Washington, D.C., on May 4, 1961, and was scheduled to arrive in New Orleans on May 17.

Supporting paragraphs: Greyhound Bus Station (Montgomery, Alabama) Freedom Riders
Answer: "Morgan v. Virginia" (1946)