Tireless crusaders vs. overzealous prosecutors
If the political polarity of these scandals were reversed, and this was all happening under a Republican Administration, the Democrat equivalent of Issa would be hailed as a "tireless crusader," not dismissed as an overzealous prosecutor. Not that a Republican Administration would have survived the Fast and Furious scandal, mind you, let alone gotten to the IRS - Benghazi - Media Crackdown Bermuda Triangle.
Likewise, concepts like "scandal fatigue" and "overreach" only exist under Democrat Presidents. The media's appetite for Republican scandals is bottomless, and no accusation can be overreach. Remember when they were holding George Bush personally responsible for Abu Ghraib? No talk of "overreach" then.
Just for fun, imagine we're reached this stage in the Mirror Universe IRS scandal, where a Republican Administration used the agency to suppress left-wing groups by searching for keywords like "progressive," "black," and "environmental." The Democrat candidate lost the 2012 election due to low turnout from his voters. Congressional Republicans defended the abuse behavior by remarking that these liberal groups were just asking for trouble by seeking the tax exemptions routinely granted to right-leaning non-profits without a fuss.
And then we find out Karl Rove was in the room when the IRS commissioner was holding an unprecedented number of meetings with the Republican president.