By Nate Anderson
August 04, 2008 - 07:31AM CT

"Committee on Energy and Commerce" and "rampage" don't often appear in the same sentence, but the House committee is certainly on a tear when it comes to behavioral advertising.

Not content with firing off a bipartisan list of sharp questions to ISPs who installed NeduAd traffic analysis hardware, the Committee on Friday expanded its nastygram list to include "33 leading Internet and broadband companies" including Google, Microsoft, Time Warner, AT&T, Verizon, and Comcast. Legislation on the issue could be coming.

The new list of recipients shows that the Committee's skepticism toward NebuAd (and ISPs Charter and Embarq, who installed the gear) wasn't a one-off deal. The Committee has expanded its investigation beyond the particular questions posed by NebuAd and is now looking far more broadly at the whole field of behavioral advertising.

Companies that make use of consumer behavior (including search queries and websites visited) to serve ads are asked to describe their practices in detail, and to explain whether they take special measures to avoid use of health, financial, or other sensitive information. In addition, the Committee wants to know if behavioral targeting is "opt out" or "opt in" and how many users chose to opt out.