A jury found one-time Democratic presidential hopeful and former Sen. John Edwards not guilty on one count of accepting illegal campaign contributions and said its deliberations had reached a standstill on five others, prompting the judge to declare a mistrial.

On its ninth day of deliberations, the federal jury in Greensboro, N.C., said today that Edwards had not violated campaign finance law by accepting money from a benefactor in 2008. The panel remained deadlocked on five other counts that included conspiracy, accepting illegal campaign contributions and making false statements to the government. U.S. District Judge Catherine C. Eagles told the jurors to continue considering the remaining counts before declaring a mistrial later in the afternoon.

The outcome is a blow to the Justice Department’s Public Integrity Section, which now must decide whether to pursue a new trial on the counts on which the jury deadlocked.

Legal scholars said federal prosecutors should pursue more clear-cut cases of public corruption now that another high-profile case against a Senator has been derailed.

The first was the botched prosecution of the late Sen. Ted Stevens. Though a jury convicted the Alaska Republican of omitting gifts he received on his Senate financial disclosure forms, a judge voided the verdict after finding that the government failed to disclose evidence favorable to the defense, as required by law. The Justice Department announced earlier this month that two government prosecutors who handled the Stevens case will be suspended without pay, though they may appeal the decision.

“I think the big point here is that the government shouldn’t overreach when it comes to going after politicians in criminal cases. There are enough cases when the law is clear cut and the facts are clear cut,” said Rick Hasen, a law professor at University of California, Irvine. “When it comes to reaching out and using the criminal law to advance theories that are new, this should be a lesson for prosecutors not to do that.”

Edwards, 58, was indicted by a federal grand jury nearly one year ago for knowingly receiving and concealing contributions of nearly $1 million from two wealth donors from 2007 to 2009. The donors, Rachel “Bunny” Mellon, the widow of billionaire philanthropist Paul Mellon, and Fred Baron, a Texas trial lawyer and prominent Democratic fundraiser, were alleged to have written sizable checks to pay for the living and travel expenses of Edwards’ mistress, Rielle Hunter, with whom he had a child.

Edwards’ legal team argued that his campaign committee did not report these donations, which far surpassed the maximum amount allowed by law, because they were private gifts intended to keep his mistress and their child a secret from his wife, Elizabeth, who died of cancer in December 2010.

Federal prosecutors said those donations were campaign contributions because Edwards’ bid for the Democratic nomination depended in part on his image as a devoted father and family man. At the time of the indictment, legal experts told Roll Call that securing a conviction in the Edwards case would require a broad reading of what constitutes a campaign finance contribution and that there was conflicting precedent in similar civil cases that have been considered by the Federal Election Commission.

“Stevens didn’t go well and this didn’t go well. It may chasten the Justice Department on going after politicians using shaky legal theories,” Hasen said.