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Reading the comment's over at Ars Technica and it occurred to me that maybe more is going on than what we are seeing on the surface. I have a couple reasons for thinking this:
1. The press conference is unusual. Usually they just forward the investigation and answer a few questions when asked.
2. The language was very harsh in comparison to the recommendations.
3. He stepped right up to the line of calling what Clinton did a felony but carefully didn't cross it, (extremely careless versus grossly negligent)
4. He admitted that others in similar circumstances would face charges / sanctions.
5. His actual recommendation. Instead of saying that they found no indication of criminal activity or didn't find enough evidence to prosecute Comey declared that "no reasonable prosecutor would file charges". Is that code for no prosecutor likely to be assigned to the case (a discretionary call) is likely to risk his career or his bosses displeasure? Or maybe he was just told we aren't filing charges so wrap it up.
Just a thought.