Eight former staff members of the U.S. House of Representatives Judiciary Committee are now lobbying on behalf of companies or groups supporting controversial copyright enforcement legislation in Congress, an example of the close ties often found between the political establishment and business interests.

The eight former staff members represent organizations that lobbied in support of the Protect IP Act (PIPA), a bill awaiting action in the U.S. Senate, according to the Sunlight Foundation Reporting Group, a government watchdog group. The House Judiciary Committee is scheduled to debate amendments to a similar bill, the Stop Online Piracy Act (SOPA), in a markup session beginning Thursday.

On the other side of the debate, two former House Judiciary staffers now lobby on behalf of Google or the Digital Media Association, two groups opposed to SOPA. Another six former staffers lobby on behalf of Microsoft, Verizon or AT&T, three companies that have expressed reservations about SOPA, the Sunlight Foundation said.

Groups and companies supporting SOPA with former House Judiciary Committee staffers lobbying for them include the U.S. Chamber of Commerce, Comcast, the Motion Picture Association of America and Viacom. Mitch Glazier, senior executive vice president at the Recording Industry Association of America, another SOPA supporter, was chief counsel to the Judiciary Committee's subcommittee on intellectual property in the late '90s, during the passage of the Digital Millennium Copyright Act.

A spokeswoman for the House Judiciary Committee did not respond to a request for comments on the Sunlight Foundation report.

The U.S. entertainment industries have long had a cozy relationship with the Judiciary Committees in the House and Senate, said Ed Black, president and CEO of the Computer and Communications Industry Association, a tech trade group opposed to SOPA. There's been a "revolving door" between entertainment industry groups and the committees and other government posts, he said.

"Clearly, other sectors without that history of a revolving door have had more difficulty being listened to," Black said.

Three of the most outspoken supporters of SOPA in Congress, Representatives Lamar Smith, a Texas Republican, Bob Goodlatte, a Virginia Republican, and Marsha Blackburn, a Tennessee Republican, all count the entertainment industries among their top campaign contributors.

Smith, the House Judiciary Committee chairman and primary sponsor of SOPA, has received US$59,300 from the television, movie and music industries in the 2011-2012 election cycle. The entertainment industry is the top industry contributing to Smith's campaign, according to OpenSecrets.org, a website that tracks campaign contributions.

Goodlatte has received $32,500 from the entertainment industry during the current election cycle, with the industry ranking second to the technology industry, with just $1,000 more in contributions to him. Several companies in the technology industry oppose SOPA.

Blackburn, representing parts of Tennessee near country music capitol Nashville, has collected $30,500 from the entertainment industry during this election cycle. Only the oil and gas industry and health professionals have contributed more to her campaign.

Staffers for Smith, Goodlatte and Blackburn did not respond to requests for comment on the campaign funding.

Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's e-mail address is grant_gross@idg.com.