Those lawmakers were among 73 members of Congress who have sponsored or co-sponsored legislation in recent years that could benefit businesses or industries in which either they or their family members are involved or invested, according to a Washington Post analysis. The findings emerge from an examination by The Post of financial disclosure forms and public records for all 535 members of the House and Senate.
The practice is both legal and permitted under the ethics rules that Congress has written for itself, which
Congress members back legislation that could benefit themselves, relatives - The Washington Post
There are a series of Washington Post articles on such conflicts of interests see: http://www.washingtonpost.com/capitolassets