They are Liars

As was noted in the Corner of National Review OnLine, and elaborated even further for its falsity at BigGovernment the whole controversy over supposed "racist" Tea Partiers is a complete and utter sham. Throw in the Rev. (ha!) Sharpton claiming to have actually seen video of the use of the N word, and then backtracking when caught in such a lie is even more evidence of their desperation. These outrageous and false accusations are a made up tempest designed to marginalize concerned citizens.
It's clear that making an accusation of someone using such a disgusting word, that the burden immediately is shifted to the accused to prove that it didn't happen. And because proving a negative is impossible, the accuser can get away scot free. Well, not anymore.
The next question has to be, why do these people stoop to such despicable tactics? In part, it's because they fear those in the Tea Party movement. Not from any actual violence, but because the Tea Partiers are no longer to be herded like the cattle they are considered to be by their accusers. They are standing up to the tyranny of the minority that claims the mantle of moral superiority even though that mantle is undeserved. In fact, not just undeserved, it has been stolen.
There is greater similarity between the Tea Partiers and the Civil Rights movement and the reactionaries like Bull Conner and the Al Sharptons in this world than people are willing to admit. The only difference is that Bull Conner wielded the "N" word as a coercive tactic to remind African Americans of their proper place (at the back of the bus, or not at the lunch counter) and Rep. Cleaver who wants to remind the Tea Partiers of their place (shut up and pay your taxes and do as we say).
Oh yeah, one other similarity between Bull Conner and those who falsely allege racism on the part of the Tea Party: They're both Democrats.