Published: Apr 01, 2011 2:13 AM EDT
Updated: Mar 31, 2011 11:13 PM EDT

WASHINGTON (AP) - Prosecutors investigating former Sen. John Edwards spent several hours Thursday re-interviewing the man who posed as the father of Edwards' out-of-wedlock baby during the 2008 presidential campaign, suggesting they are weighing the strength of their chief witness before deciding whether to indict the former candidate.

Andrew Young met with the prosecutors in his attorney's Washington office for more than four hours. The Associated Press spotted him leaving the building's underground garage in a vehicle with a North Carolina license plate registered to his wife, Cheri, at their home in Chapel Hill.
 
The interview is particularly notable because of its timing. Young has already been questioned by a grand jury investigating Edwards in 2009 and the Justice Department is considering whether to move forward with an indictment.
 
Justice Department officials requested the meeting, according to a person familiar with the investigation, who requested anonymity to discuss a legal matter.
 
The prosecutors could be interested in taking a closer look at Young to see how he'll hold up as a witness, since his credibility has been challenged. Young, who was an aide to Edwards' 2008 presidential campaign, initially claimed he was the father of the child and traveled around the country helping keep Edwards mistress Rielle Hunter hidden. He has since come out with a book detailing the lengths Edwards and his allies went to cover up the affair and child. The book is being turned into a Hollywood film.
 
Around the time the book was released, in January 2010, Edwards came forward to acknowledge that he had fathered the girl, Frances Quinn Hunter.
 
Rielle Hunter also sued Young around the time he was releasing the tell-all. Her attorneys aggressively questioned his credibility then, and a North Carolina judge said he was troubled by a series of seemingly conflicting statements that Young made under oath in the lawsuit involving a purported sex tape depicting Edwards. Superior Court Judge Abraham Penn Jones considered sending Young to jail for contempt but backed away as Young's attorneys argued that the discrepancies were memory lapses. Young has said he had the sex tape simply to corroborate his story.
 
Young's attorney, David Geneson, did not return a call for comment on the meeting, and the Justice Department declined to comment.
 
The investigation centers on the money spent to keep Hunter and Young in hiding. Investigators are looking chiefly at whether funds paid to Hunter and Young - from outside political groups and Edwards' political donors - should have been considered campaign donations since they arguably aided his presidential bid, according to several people involved in the case who have described it on condition of anonymity because of the ongoing probe.
 
Young would be their chief witness from inside the money exchanges, since one donor who gave them money has died and the second is 100 years old.
 
The investigation is being jointly run by the Republican-appointed U.S. attorney in Raleigh and the public integrity section of Justice Department in Washington. The Justice Department has reason to be cautious in pursuing the case after the public integrity section's last prosecution of a high-profile politician, the late Alaska Republican Sen. Ted Stevens, ended so badly. A judge overturned Stevens' conviction and ordered a criminal investigation into the prosecutors' conduct after the department admitting its lawyers did not turn over important, exculpatory evidence to the defense team.

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