GREENSBORO, N.C. — The federal judge overseeing the criminal trial of John Edwards will sharply curtail the testimony of a key defense witness who could have raised doubt about whether the former presidential candidate broke campaign finance laws.
Mr. Edwards' lawyers had intended to call former Federal Election Commission Chairman Scott E. Thomas as their first witness Monday morning, but prosecutors objected.
U.S. District Judge Catherine C. Eagles sent the jury home early so she could listen as Mr. Thomas answered questions to preview his intended testimony.
Mr. Thomas said it was his opinion that nearly $1 million secretly provided by two campaign donors and used to hide the Democrat's then-pregnant mistress while he sought the White House in 2008 did not qualify as federal campaign contributions under existing federal law.
"These are intensely personal, by their very nature," said Mr. Thomas, who served on the FEC from 1986 to 2006 after appointments by Presidents Ronald Reagan, George H.W. Bush and Bill Clinton. "In my view this is a clear-cut case that the payments were not campaign contributions."
Mr. Thomas cited past cases before the FEC to support his position, including a $96,000 payment in 2008 by the parents of then-Republican Sen. John Ensign of Nevada to his then-mistress that was later determined not to have violated the law.
Mr. Thomas also said federal election law was so complicated that reasonable and knowledgeable people can disagree about whether something qualifies as a political contribution. To win a conviction under the law, prosecutors must show not only that Mr. Edwards knew about the scheme but also that he knew he was violating the law.
But the jury deciding Mr. Edwards' fate will not hear any of that testimony, which supports the defense position that the secret payments benefiting Mr. Edwards' then-mistress Rielle Hunter were gifts from his wealthy friends, not political contributions intended to aide his presidential candidacy.
Judge Eagles agreed with prosecutors that Mr. Thomas' personal opinions and past FEC rulings are irrelevant to their criminal prosecution of Mr. Edwards.
Judge Eagles said she would allow Mr. Thomas to take the stand, but barred nearly all of his expected testimony.
Lead defense lawyer Abbe Lowell appeared incredulous as he asked Judge Eagles for further explanation of her ruling, which he suggested flew in the face of established case law. He warned that the limits amounted to "reversible error" that might be overturned on appeal.
The judge responded by chastising Mr. Lowell for what she perceived as his disrespectful tone.
The exchange came after 14 days of testimony from prosecution witnesses who recounted the lurid details of the extramarital affair carried on by Mr. Edwards while his wife Elizabeth battled terminal cancer. She died in late 2010.
Mr. Edwards has pleaded not guilty to six criminal counts including conspiracy to violate the Federal Election Campaign Act, accepting contributions that well exceeded campaign finance limits, and filing false campaign finance statements. He faces up to 30 years in prison if convicted.