The killings of James Chaney, Michael Schwerner and Andrew Goodman in Neshoba County 57 years ago sparked a wave of national grief and outrage, leading to the passage of the 1964 Civil Rights Act.
And now, the previously sealed materials on the investigation into their deaths, which date from 1964 to 2007 and include research notes, witness testimonies and photographs, among other records, have been made available for public viewing at the William F Winter Archives and History Building in Jackson.
The three men, who were all in their 20s and part of the Freedom Summer Project, an effort to attempt to register as many black voters as possible in Mississippi, had been investigating the burning of a black church near Philadelphia, Mississippi when they went missing in June of 1964.
They had been arrested by a Neshoba County Deputy Sheriff named Cecil Price for allegedly speeding on the afternoon of 21 June, according to the FBI.
Shortly after their release, they were followed by members of the Ku Klux Klan in what the FBI called a “preordained plan”. The three men were never heard from again.
The case went on to become known as “Mississippi Burning” after investigators found the station wagon the three men were believed to have been travelling in charred.
Eventually, however, agents acting on an informant tip were able to locate and exhume the bodies of all three men from below a dam on a local farm.
All three men had appeared to have been badly beaten and shot at point blank range.
More than a dozen suspects, including Deputy Price and his boss Sheriff Rainey were indicted and arrested. After years of courtroom battles, seven of 18 defendants were found guilty, including Price, but not on murder charges.
One individual, Edgar Ray Killen, a Baptist preacher, was eventually convicted of manslaughter on 21 June 2005, the 41st anniversary of the slayings.
Previously, Killen had been able to walk free after one juror refused to convict a Baptist preacher, according to the FBI.
Then-Mississippi attorney general Jim Hood officially closed the investigation into the three deaths in 2016, with Killen dying in prison two years later in 2018.