The family of the late, disgraced Penn State football coach is filing a new lawsuit, this one against the NCAA, centered around what it believes was a faulty investigation by Louis Freeh.

By Daniel Roberts, writer-reporter

Please see update below.

Joe Paterno and his wife at the 1975 Cotton Bowl.

FORTUNE -- Nearly a year after the release of the Freeh Report on child abuse at Penn State University, the family of deceased coach Joe Paterno is still refuting its conclusions and will bring a new lawsuit against the NCAA.

On Wednesday evening, a group representing the family will announce the lawsuit on NBC Sports Network's Bob Costas Tonight. The suit will bring renewed scrutiny to the investigative work of former FBI director Louis Freeh, who was hired by PSU's board of trustees. "What this does," Paterno family lawyer and spokesman Dan McGinn told Fortune, "is force the NCAA to have him talk under oath and explain what really happened."

The lawsuit -- which is not just a family lawsuit but is being filed on behalf of a broad constituency of individuals, including former board members, players, and coaches -- has two purposes: to clear Paterno's name, obviously, but also to strip Freeh's process bare in a court of law. The family wants to know exactly who Freeh and his people interviewed, what they told those people, what Freeh has in his notes from the case, and whether those who spoke to Freeh were misled in any way. What those behind the lawsuit want, McGinn says, is "to overturn the NCAA's unlawful actions."

The family feels that it should have been given the opportunity to respond to the report ahead of time; once it was already out, McGinn says, it was too late, and the media had already painted a certain picture of Paterno's alleged negligence. But Freeh tells Fortune that there was a key reason for their choice to release the report online at the same time it gave it to the PSU board: "The reason for that was to ensure the independence of the product, both for the investigator, but also, to its credit, the board."

This new lawsuit builds on contentions already made by this same group over the past few months. In February, Paterno's family released an official rebuttal to the Freeh Report, supported by "independent experts" like former attorney general Dick Thornburgh and attorney and former FBI agent James Clemente. That report, entitled "The Rush to Injustice Regarding Joe Paterno," charged that Freeh's findings (that Paterno and other PSU officials willfully kept quiet about misconduct by Jerry Sandusky that they knew was occurring) were hasty and had "inaccurate and unfounded" parts to it.

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The rebuttal prompted Louis Freeh, now chairman of his own investigations business Freeh Group International Solutions, to issue a statement in response. Freeh, who has been hired for other high-profile engagements such as serving as bankruptcy trustee for the liquidation of MF Global, normally refuses to comment on an issue once his report is out. But Thornburgh's involvement was the impetus. "They were fairly serious allegations, and we respectfully but factually just put down a response to that," Freeh told Fortune in an interview last month. "But that was a very unusual exception. It was the former Attorney General of the United States."

In the statement, released the same day, Freeh noted that Paterno "was willing to speak with a news reporter and his biographer at that time" -- a slight dig, it would seem -- but "elected not to speak with us." He defended his report ("I stand by our conclusion that four of the most powerful people at Penn State failed to protect against a child sexual predator harming children") and added, in an asterisked note, that in 1989 Thornburgh tapped Freeh to lead the investigation into the mail-bomb murder of Alabama federal judge Robert Smith Vance, and at that time, "highly praised my investigative abilities."

Indeed, it is somewhat ironic that the two main figures in these Paterno family accusations are Thornburgh and Clemente, both of whom had worked with Freeh in the past and had positive relationships with him. "They both admired him," McGinn told Fortune. "But they feel that Louis Freeh and his investigators literally got it wrong the first day out of the box. They made bad assumptions, and they went down the wrong road … and treated this like a prosecution of another kind."

The board, meanwhile, chose not to appeal any of the punishments (fined $60 million, stripped of all titles since 1998, and banned from bowl games for four years) meted out in the wake of the Freeh Report. But maybe it didn't have to: The Paterno family's suit, if successful, may result in changes to those NCAA sanctions.

UPDATE: In a statement sent to Fortune by email, NCAA chief legal officer Donald Remy said, "Despite our request, the Paterno family has not shared any information about its planned legal action. Therefore we are unable to comment further about that at this time."