I disagree. AG Lynch met Bill Clinton and told him she would take care of the email thing. FBI Comey went outside normal procedure, playing investigator AND prosecutor, giving Hillary a pass on jeopardizing national security by careless handling off classified material.
I see that as a lack of intestinal fortitude on Comey's part, perhaps a justified fear, considering those who cross the Clinton machine have had a bad habit of waking up dead in the morning if they can't make the jump from relative obscurity to the limelight with their information in very short order. Because it was an investigation, knowledge of wrongdoing on the Clinton's part could be buried right along with him. The departure form his job description would have been to go public with the info or to try to prosecute (not his job). Consider Obama has been front man for the Clintons, and was the 'warm up act' for Hillary's presumed tenure, and you get the picture.
In an nutshell, Comey didn't want to do a Ron Brown/Vince Foster/Bill Colby/etc.
But he was between his job and a hard place, and the only way to get out of it was to either drag out the 'investigation' and run out the clock, or to conclude the investigation and pass off the results to a DOJ which would not have prosecuted Hillary for the vivisection of young children on the White House lawn in broad daylight at the height of tourist season. He did the latter (passed it on to the DOJ and Lynch) and lived. Bubba had a 'talk' with Lynch, and the matter went away.
Did Comey have partisan leanings? Possibly, but my bet is on just wanting to live through that and get to retirement is good enough shape to keep his job and enjoy his check.