Raleigh, N.C. — The North Carolina attorney general has asked federal prosecutors to help conduct a criminal probe into former District Attorney Mike Nifong and others involved in the now-defunct Duke lacrosse case.

That's according to a letter that Charlotte defense attorney James Cooney III sent to acting U.S. Deputy Attorney General Craig S. Morford urging that the federal government assist.

Cooney, Reade Seligmann's former defense attorney, would not comment to the matter or the letter, which he also sent a copy to Jim Coman – one of two special prosecutors who evaluated the case.

"The attorney general of North Carolina simply does not have the investigative tools that are at the command of the federal government, including the ability to convene an investigating grand jury," Cooney, Reade Seligmann's former defense attorney, wrote.

"Participation by the government of the United States in an investigation with North Carolina authorities is critical to any full, fair and open evaluation of the facts of this case," he continued.

Seligmann, along with Collin Finnerty and David Evans, faced charges of rape, sexual assault and kidnapping after an exotic dancer claimed she was raped, sodomized and beaten in a bathroom at a party in March 2006.

The three men were later cleared of all charges and have since filed a federal lawsuit against Nifong and the city of Durham.

In September, acting Durham County District Attorney Jim Hardin asked the attorney general's office to consider a criminal probe into the handling of the case.