Biased justice

This morning Paul Krugman [behind subscription wall] reports a new finding that adds further evidence to the claim that the Department of Justice has been using its power to go after Democrats:

Donald Shields and John Cragan, two professors of communication, have compiled a database of investigations and/or indictments of candidates and elected officials by U.S. attorneys since the Bush administration came to power. Of the 375 cases they identified, 10 involved independents, 67 involved Republicans, and 298 involved Democrats. The main source of this partisan tilt was a huge disparity in investigations of local politicians, in which Democrats were seven times as likely as Republicans to face Justice Department scrutiny.

Now, I suppose our Republican friends would think it natural that seven times as many Democrats were targeted. "After all, aren't Democrats more corrupt?" they would probably say.
Somehow that doesn't seem to be borne out by the more prominent cases that don't fly beneath the media's radar screen though, does it? It sure seems as though the big busts have almost all been of Republicans during the past six years. I wonder how many more there would have been if the DOJ wasn't wielding a politically biased weapon.