The CDC came under fire this week after we broke news they had deleted defensive gun use (DGU) stats from their website under pressure from gun-control advocates. It's an extremely important story, but one that involves some complicated science.

So, I wanted to bring on somebody who has extensive knowledge of the topic to help us get a better understanding of the controversy. That's why I asked Manhatten Institute fellow Robert VerBruggen to join me. He has written about the strengths and weaknesses of different methods for estimating DGUs, including the Gary Kleck surveys at the center of the fight.

He said the real problem with the CDC ordeal is that it raises ethical questions which cast a shadow over the agency's reputation. He said officials should not have consulted with gun-control advocates in secret and to the exclusion of other outside perspectives. VerBruggen noted there was no new information shared during the conversations with the advocates, and the initial language the CDC scrubbed from their website was not inaccurate.

VerBruggen said there are legitimate critiques of using surveys to calculate DGUs. The media-report-based estimate that gun-control advocates prefer is even more problematic, according to VerBruggen. He explained the ins and outs of the different approaches and why they produce such divergent results.

Plus, Contributing Writer Jake Fogleman and I discuss the political fallout from the CDC's actions.

Special Guest: Robert VerBruggen.