"At the same time NRA2BFree assures us that Barney Frank is NOT INVOLVED with a child."
The difficulty with your point is the implicit thought that if we can find someone on the other side who is more bad than we may not appear as bad in this matter.
If we follow this approach we crawl into a moral sewer. The only valid position is to condemn unethical behavior as unethical.
Still, we should not cover up for Barney if, in fact, he is engaged with a child simply because we don't look like we are doing so for reasons of political retaliation.