Tying the noose a little tighter......

....is White House spokesman David Plouffe, who is responding to the sworn testimony of the IRS agents involved in the illegal screening of Tea Party groups (not to mention a bunch of others) by pointing to events in Issa's life for which he was exonerated prior to a trial being convened.

When your opponent responds to sworn evidence with unrelated personal attacks, that indicates he's either unwilling or unable to come up with substantive evidence.  It means his case is weak.  Again, it's time for an independent prosecutor to sort this out, as it's pretty obvious that the White House isn't going to.