The Mississippi Sovereignty Commission (MSC) was one of many agencies established by southern states to resist desegregation.
It was reputed to be one of the most zealous in its efforts to track down and discredit civil rights activists, and has been compared to the Stasi, East Germany's secret police.
The information collected by the MSC was given to police and employers, but much of it was also passed to the Ku Klux Klan who conducted a reign of terror against civil rights activists.
Almost all of the 132,000 pages of documents produced, from the agency's founding in 1956 until it disbanded 21 years later, have been made available, having been kept under lock and key for more than 20 years.
Unsolved murders
The archive's contents are explosive. There is information on 17 of the 18 unsolved murders of civil rights activists, as well as surveillance reports by informants who infiltrated civil rights groups and the voting records of politicians on issues affecting segregation.
![[ image: width=150]](/olmedia/65000/images/_66754_vernon_dahmer150.jpg)
Scores of people queued to get into the Mississippi Department of Archives and History where the files are now available.
One of the first people to view the files was Vernon Dahmer Jr who was looking for more information on the murder of his father. Mr Dahmer Sr was burned alive when the Ku Klux Klan firebombed his home and shop. His 'crime' was helping fellow blacks to get the vote.
Three separate files deal with the case of Mack Charles Parker, a black Mississippian lynched 32 years ago, allegedly because he flirted with a white woman.
Black cynicism
"I'm relieved it has finally happened," said David Ingebretsen, the executive director of the American Civil Liberties Unions (ACLU), who led a 20-year court fight to force the state to open the files.
"It's a story of very courageous people, ordinary people who stood up for their rights against all the powers that the state could muster to deny them those rights," he said.
"It was virtually a police state back then."
However, some people are cynical about the exercise.
"The general reaction among blacks is that the real stuff is not in there - that a lot of things were blotted out, and that this won't have a great impact," said Latifa Turner, whose grandfather was a lawyer for Martin Luther King.
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