In the final, frenetic days of Georgia's 2010 GOP runoff, a bombshell dropped: Word that a federal grand jury in Atlanta demanded information seemingly related to Nathan Deal's actions as a member of Congress.

The campaign of Deal's opponent in the race for governor, Karen Handel, used the news to suggest that Deal -- already the subject of a congressional ethics investigation -- was also the target of a criminal probe. Deal denied that and went on to win the runoff and the fall election.

Now nearly two years later, Deal has named the federal prosecutor who signed the grand jury subpoena to a judgeship. In February, Deal appointed Robert McBurney, then head of the the public corruption unit in the U.S. Attorney's Office in Atlanta,  to a vacant seat in Fulton County Superior Court.

The pick has revived the never-answered question of what -- if anything -- federal prosecutors were investigating related to Deal. In interviews with The Atlanta Journal-Constitution, McBurney made comments that could be interpreted as suggesting that whatever probe once existed is no longer active. However, both he and Justice Department officials refused to depart from the agency's policy of not acknowledging that an investigation has been closed.

In the absence of a definitive answer, McBurney's appointment has left some political veterans scratching their heads. Melanie Sloan, a former federal prosecutor who is executive director of Washington-based Citizens for Responsibility and Ethics, called the selection "highly unusual."

“To appoint someone to a judgeship who has been investigating you? It certainly looks strange,” Sloan said.

McBurney, 44, told the AJC  he sought and received clearance from top officials in the U.S. attorney's office before applying for the $162,000-a-year judicial post. Agency officials reviewed all his active cases and found no conflict of interest, he said.

"At the time I considered applying for the opening ... I had not worked on the matter that generated the subpoena for many months," he said, adding that even when he was investigating he was "not the substantive decision maker."

Still, he acknowledged that, to an outsider, "I could see how there could be the appearance of a conflict."

Deal's lawyer, Randy Evans,  said McBurney's role in whatever the grand jury was investigating never came up during the judicial vetting process.  The reason? Evans said he forgot all about it.

“I didn’t remember it until you just brought it up,” said Evans, who also serves as co-chairman of a panel that recommends judicial picks to the governor. He told the AJC the governor was equally oblivious to the connection. "The governor would have known even less than I did."

The Judicial Nominating Commission considered 24 candidates for the seat and culled the applicants down to four finalists -- including McBurney --whose names were forwarded to the governor.

Deal's office called McBurney the best man for the job.

"His resume speaks for itself," Deal spokesman Brian Robinson said. "His credentials are impeccable."

McBurney is widely regarded as a legal star. An honors graduate of Harvard College and Harvard Law School, he worked as a Fulton County homicide prosecutor before he left to take a job with the feds in 2002.

He worked for nearly a decade in the U.S. Attorney's Office in Atlanta, rising to become senior litigation counsel, and initiated the high-profile trial of four militia members for conspiracy to acquire explosives.

"I think Robert is a great prosecutor and a very ethical person who works very hard to do what's right," said lawyer Aaron Danzig, who worked alongside McBurney for five years in the U.S. Attorney's Office.

In 2010, McBurney became coordinator of the office’s public corruption caseload, which is how his path seemed to collide with Deal's.

Questions about then-congressman Deal's ethics first emerged in 2009, when The Atlanta Journal-Constitution detailed meetings between him and Georgia Revenue Commissioner Bart Graham.  The revenue commissioner was seeking to change the way the state inspected rebuilt cars, and Deal owned a Gainesville auto salvage business that provided space to perform the inspections.

The AJC article prompted a probe by the Office of Congressional Ethics, which found that Deal may have violated U.S. House rules. In the meetings -- described by one participant as hostile --  Deal intervened to protect a lucrative arrangement between his business and the state, the ethics panel found. Deal countered that he was acting as a public servant and was concerned about highway safety if the program was altered.

Deal resigned from the House in March 2010 before the panel could take any formal action. At the time, he said he wanted to devote himself full-time to the race for governor. His political opponents suggested he left to avoid ethics charges.

Then, on May 24, McBurney signed a federal subpoena ordering Graham to appear before a grand jury on June 8 and hand over documents related to a conversation with Deal that took place after a one of their meetings. Records show that the same day the subpoena was issued, McBurney and an FBI agent met with Graham in his Department of Revenue office.

The subpoena and the meeting became public on July 27 through an AJC open records request. That was just two weeks before the primary runoff.

Despite the Handel campaign's barbs, Evans at the time insisted his client was not the target or subject of a federal probe. Federal investigators declined to comment. Graham has also refused to comment. With no new information, the matter faded from view once the campaign was over.

McBurney's appointment sends the strongest signal yet that any federal interest in Deal has waned.

McBurney told the AJC that before he applied for the Fulton County Superior Court seat he consulted with top officials in his office, including U.S. Attorney Sally Yates.  He said he and his bosses conducted separate reviews of the active cases of the public corruption unit and separately determined there was no conflict that would prevent him from seeking the appointment from Deal.

"There was a consensus that there was no problem, there was no conflict," McBurney told the AJC.

Asked if that meant there was no active probe of Deal, McBurney replied, "you can deduce from that what you will."

The U.S. Attorney's Office was more circumspect.

“Robert notified us of his application for the judgeship, and we were mindful of any potential conflict issues -- as we would be of any prosecutor who seeks outside employment or this kind of employment,” spokesman John Horn said.

Evans said the mere fact that McBurney applied for the bench proves that the supposed investigation of Deal was a fiction. "There was never anything to it. It was all nonsense," he said.

-- Staff writer James Salzer contributed to this report.