According to this article from The New Yorker, Comey went rogue and defied the wishes of his boss, Attorney General Loretta Lynch.
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Comey’s decision to make public new evidence that may raise additional legal questions about Clinton was contrary to the views of the Attorney General, according to a well-informed Administration official. Lynch expressed her preference that Comey follow the department’s longstanding practice of not commenting on ongoing investigations, and not taking any action that could influence the outcome of an election, but he said that he felt compelled to do otherwise.
Comey’s decision is a striking break with the policies of the Department of Justice, according to current and former federal legal officials.
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“You don’t do this,” one former senior Justice Department official exclaimed. “It’s aberrational. It violates decades of practice.”
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Traditionally, the Justice Department has advised prosecutors and law enforcement to avoid any appearance of meddling in the outcome of elections,
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Four years ago, then Attorney General Eric Holder formalized this practice in a memo to all Justice Department employees. The memo warned that, when handling political cases, officials “must be particularly sensitive to safeguarding the Department’s reputation for fairness, neutrality, and nonpartisanship.”
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According to the Administration official, Lynch asked Comey to follow Justice Department policies, but he said that he was obliged to break with them because he had promised to inform members of Congress if there were further developments in the case.
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As Miller sees it, Comey’s “original sin” was the press conference he held in July regarding the Clinton e-mail investigation.
Now ask yourself, if you defied the wishes of your boss at work and deliberately violated the departments policies, and you took an action that had an unbelievable negative impact on your department, the company, the country, and the world, and this wasn’t the first time you did it, what would happen to you?! You would get fired, and rightfully so, and that’s exactly what should happen to Comey.