Question: United States v. Cecil Price, et al., also known as the Mississippi Burning trial, was a criminal trial where the United States charged a group of 18 men with conspiring in a Ku Klux Klan plot to murder three young civil rights workers (Michael Schwerner, James Chaney, and Andrew Goodman) in Philadelphia, Mississippi on which date, the murders of Chaney, Goodman, and Schwerner, also known as the Freedom Summer murders, involved three activists that were abducted and murdered in Neshoba County, Mississippi, during the Civil Rights Movement?

Context paragraphs:
Rita Schwerner Bender: Rita Levant Schwerner Bender (born 1942) is a civil rights activist and lawyer.  She and her first husband Michael (Mickey) Schwerner participated in the Freedom Summer of 1964, where Michael was murdered by the Ku Klux Klan.  As his young widow, she drew national attention for her commentary on racial prejudice in the United States, delivered at a press conference after her husband went missing.  After the Civil Rights Movement, Schwerner became an attorney, now practicing family law in Washington state.  She continues to advocate for civil rights today through her law practice and public presentations.

Samuel Bowers: Samuel Holloway Bowers (August 25, 1924 – November 5, 2006), Former Ku Klux Klan Imperial Wizard, was a convicted murderer and leading white supremacist activist in Mississippi during the Civil Rights Movement.  In response to this movement, he co-founded a reactionary organization, the White Knights of the Ku Klux Klan.  Bowers committed two notorious murders of civil rights activists in southern Mississippi: The 1964 murders of Chaney, Goodman, and Schwerner near Philadelphia, for which he served six years in federal prison; and the 1966 murder of Vernon Dahmer in Hattiesburg, for which he was sentenced to life in prison 32 years after the crime.  He also was accused of bombings of Jewish targets in the cities of Jackson and Meridian in 1967 and 1968 (according to the man who was convicted of some of the bombings, Thomas A. Tarrants III).  He died in prison at the age of 82.

United States v. Price: United States v. Cecil Price, et al., also known as the Mississippi Burning trial or Mississippi Burning case, was a criminal trial where the United States charged a group of 18 men with conspiring in a Ku Klux Klan plot to murder three young civil rights workers (Michael Schwerner, James Chaney, and Andrew Goodman) in Philadelphia, Mississippi on June 21, 1964 during Freedom Summer.  The trial, conducted in Meridian, Mississippi with U.S. District Court Judge W. Harold Cox presiding, resulted in convictions of 7 of the 18 defendants.

James Chaney: James Earl Chaney (May 30, 1943 – June 21, 1964), from Meridian, Mississippi, was one of three American civil rights workers who were murdered during Freedom Summer by members of the Ku Klux Klan near Philadelphia, Mississippi.  The others were Andrew Goodman and Michael Schwerner from New York City.

Edgar Ray Killen: Edgar Ray "Preacher" Killen (born January 17, 1925) is a former Ku Klux Klan organizer who planned and directed the murders of James Chaney, Andrew Goodman, and Michael Schwerner, three civil rights activists participating in the Freedom Summer of 1964.  He was found guilty in state court of three counts of manslaughter on June 21, 2005, the forty-first anniversary of the crime, and sentenced to 60 years in prison.  He appealed against the verdict, but the sentence was upheld on January 12, 2007, by the Mississippi Supreme Court.

Lawrence A. Rainey: Lawrence Andrew Rainey (March 2, 1923 – November 8, 2002) was the elected Sheriff of Neshoba County, Mississippi from 1963 to 1968.  He gained notoriety for allegedly being involved in the June 1964 murders of Chaney, Goodman, and Schwerner, as depicted in the movie "Mississippi Burning" (1988).  He was also a member of the Ku Klux Klan.

Murder in Mississippi: Murder in Mississippi is a 1990 television film which dramatized the last weeks of civil rights activists Michael "Mickey" Schwerner, Andrew Goodman and James Chaney, and the events leading up to their disappearance and subsequent murder during Freedom Summer in 1964.  It starred Tom Hulce as Schwerner, Jennifer Grey as his wife Rita, Blair Underwood as Chaney, and Josh Charles as Goodman.  Hulce received a nomination for Best Actor in a TV Miniseries at the 1990 Golden Globes.

Mississippi Burning: Mississippi Burning is a 1988 American crime thriller film directed by Alan Parker, and written by Chris Gerolmo.  It is loosely based on the FBI's investigation into the 1964 Chaney, Goodman and Schwerner murder case in Mississippi.  The film stars Gene Hackman and Willem Dafoe as two FBI agents assigned to investigate the disappearance of three civil rights workers in fictional Jessup County, Mississippi.  The investigation is met with hostility and backlash by the town's residents, local police and the Ku Klux Klan (KKK).

Carolyn Goodman (psychologist): Carolyn Elizabeth Goodman (née Drucker; October 6, 1915 – August 17, 2007) was a clinical psychologist who became a prominent civil rights advocate after her son, Andrew Goodman and two other civil rights workers, James Chaney and Michael Schwerner, were murdered by the Ku Klux Klan in Neshoba County, Mississippi, in 1964.

Murders of Chaney, Goodman, and Schwerner: The murders of Chaney, Goodman, and Schwerner, also known as the Freedom Summer murders, the Mississippi civil rights workers' murders or the Mississippi Burning murders, involved three activists that were abducted and murdered in Neshoba County, Mississippi in June 1964 during the Civil Rights Movement.  The victims were Andrew Goodman and Michael "Mickey" Schwerner from New York City, and James Chaney from Meridian, Mississippi.  All three were associated with the Council of Federated Organizations (COFO) and its member organization the Congress of Racial Equality (CORE).  They had been working with the Freedom Summer campaign by attempting to register African Americans in Mississippi to vote.  This registration effort was a part of contesting over 70 years of laws and practices that supported a systematic policy of disenfranchisement of potential black voters by several southern states that began in 1890.

Supporting paragraphs: United States v. Price Murders of Chaney, Goodman, and Schwerner
Answer: June 21, 1964