Let's see: Michael Chertoff was head of the TSA, oversaw the decision about the safety of the scanners, and held a financial interest in the company that made the scanners.
The Huffington post claims Chertoff's company was doing undisclosed public PR for Rapiscan's equipment in The Washington Post, etc. misrepresenting the capabilities of their equipment, which the WP partially confirmed: http://www.washingtonpost.com/wp-dyn/content/article/2009/12...
Rapiscan denies that they hired him to as a government lobbyist, so they're very specifically denying something other than what they're being accused of.
Sounds legit, nice work Mike.