Politifact, the lauded political ad fact-checking operation, labels Sen. Blanche Lincoln's latest ad on John Boozman's advocacy of a 30 percent national sales tax as a half-truth because it doesn't mention the sales tax would replace the income tax.
A couple of things:
1) Some earlier versions of Lincoln's ad did explicitly say the sales tax would replace the income tax.
2) If all ads are required to include opponent's rebuttal of criticism and furthermores to be fully true, then most of them are half-truths to some degree. Furthermore, this one is a bit more than a half truth. Millions of Americans have no income tax liability. For them, a national sales tax will be a new levy with no offset. (Some of them will lose an earned income tax credit in the "bargain.") It is a wrenching, crazy idea with cataclysmic potential up and down the commercial chain. Boozman has sponsored it. Lincoln's ads say he sponsored it. Both assertions are 100 percent true. If anything, she's cut him a break by calling it a 23 percent tax instead of 30.