FBI Director James Comey likely declined to recommend Hillary Clinton be prosecuted for handling classified information on a private email server because he was not confident prosecutors would be able to secure a conviction, former FBI Assistant Director Ron Hosko said Wednesday.

However, Hosko acknowledged critics of the decision will struggle with how Comey interpreted a federal statute under which Clinton could have possibly been prosecuted for gross negligence in handling sensitive material.

"Jim Comey is a man of conscience," Hosko, who has worked under Comey, told CNBC's "Squawk Box" on Wednesday. "He has impeccable morality and ethics. His arrow points true north."

But Comey is also a former prosecutor, Hosko said, and because investigators did not find intent to cause harm or reap personal gain from the transmission of classified documents, he did not see a path to a successful prosecution.

"For an indictment you need probable cause, but prosecutors and investigators are looking for far more. You're looking down the road at a substantial likelihood of success at trial that's beyond a reasonable doubt," he said.

Indeed, Comey said Tuesday "no reasonable prosecutor" would pursue such an action.



Despite his defense of Comey's character and justification for why he didn't recommend prosecution, Hosko said he believes the elements for indictment were clearly met based on a cold read of the federal statute to which Comey referred.