John Durham, U.S. attorney for the District of Connecticut. Courtesy photo.

Amid widespread reports that Connecticut-based U.S. Attorney John Durham's investigation into the origins of a probe into Russian influence in the 2016 U.S. presidential election has evolved into a criminal investigation, we look back at our report, "Five Things to Know About John Durham," which ran shortly after he was chosen by Attorney General William Barr to head up the investigation.

First reported by the New York Times, the move to a criminal investigation means Durham will be able to subpoena witnesses, impanel juries and file charges based on his findings.

The  following is a short background summary on Durham, who's had a four-decade-long career as a federal prosecutor, and is now known as the key official who is "investigating the investigation."

1. Durham prosecuted the Boston Mob.

A Republican, Durham is the 52nd U.S. attorney for the District of Connecticut. He began in his role as the lead federal prosecutor in that state in February 2018.

He has been a Justice Department attorney since 1982. He is a former acting U.S. attorney and deputy U.S. attorney, and was chief of the Criminal Division. He also once headed the New Haven field office and the Boston Strike Force on Organized Crime, and was involved in special investigation projects under four attorneys general.

In 2002, Durham helped secure the conviction of retired FBI agent John Connolly Jr., who was sentenced to 10 years in prison on federal racketeering charges tied to his relationship with well-known mobster James "Whitey" Bulger.

2. He led investigations into a former Connecticut governor.

Durham also helped prosecute former Republican Connecticut Gov. John Rowland, who served two prison stints for not paying taxes and accepting $107,000 in gifts from people doing business with the state. He was also responsible for prosecuting mobsters in the Boston area, and led an inquiry into allegations that FBI agents and Boston police had ties with the mob.

3. He investigated the Central Intelligence Agency.

In 2009, then-Attorney General Eric Holder, a Democrat, appointed Durham to lead the Justice Department's investigation into the legality of the CIA's use of "enhanced" interrogation techniques.

4. Durham's reputation as nonpartisan made him Barr's 'surprise choice.'

Those who know Durham said they are surprised that Barr, who many view as a partisan Trump ally, would pick a prosecutor who is reputed not to allow politics to enter into his work.

"Frankly, I'm very surprised Barr picked John Durham," attorney and ethics expert Jamie Sullivan said. "Like [Robert] Mueller, Mr. Durham has an impeccable reputation. Barr did not pick someone who is in any way political."

Sullivan, a managing partner with Hartford-based Howard, Kohn, Sprague & FitzGerald and the co-author of a book on Connecticut legal ethics, added that Durham has a reputation for being "extremely tenacious and skilled and driven to come to the correct result."

"He gives the process integrity," Sullivan said.

For instance, when Durham conducted his investigation of Rowland, who had been a popular and well-liked governor, both men were staunch Republicans, Sullivan said.

"There was no political basis of any kind in that investigation and prosecution," he said.

5. Observers say he permits no leaks.

Stan Twardy Jr., Day Pitney partner and U.S. attorney for Connecticut from 1985 to 1991, has known Durham for more than three decades and says the career prosecutor "is straight down the middle."

"He is a person of tremendous integrity and is completely apolitical," Twardy said Tuesday. "He does not have a political bias in any way. … He avoids it by keeping his head down and conducting the investigation without leaks. He is as close to Bob Mueller as anyone can be. He will conduct the investigation thoroughly."

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