Lawmakers subpoena 9 food testing companies. (MSNBC)

Lawmakers voted Thursday to subpoena nine companies responsible for analyzing the most dangerous food entering the country as part of an investigation that gained more urgency with an outbreak of salmonella from tomatoes.

Stupak said nine of 10 companies declined to submit information voluntarily out of concern that the food import companies that hire them would then sue them for breaching confidentiality agreements. The records sought related to testing of food found not to meet FDA standards for import into the U.S.

Another “free” market success story.