Captured Tues., June 23, 2009, 1:30 AT

If anyone needed evidence of the value of a competitive news industry, the Guardian provided it last week.

Its rival the Telegraph had uncovered the biggest British political scandal in decades by revealing widespread abuses in MPs’ expense claims. But the Guardian took the investigation to a new level last Thursday.

The British newspaper media outlet announced it was launching a site to crowdsource the analysis of expense records — 700,000 individual documents released by House of Commons. The records represent four years of expenses for all 646 members of parliament. The Guardian’s site offers “citizen journalists” the opportunity to comb each of a half million claims and recommend it for further investigation. On Sunday, the Guardian reported that nearly 20,000 people had examined 160,000 records.

The effort is easily the most ambitious attempt at crowdsourcing ever. Vancouver-based public policy blogger David Eaves points out three benefits:

1. the analysis would have been impossible otherwise
2. it has created a new benchmark of accountability for members of elected office
3. it has provided the Guardian a strong level of engagement with its readers

As Jay Rosen learned with Assignment Zero, crowdsourcing isn’t easy. That’s why comments by the Guardian’s developer on the project, Simon Willison, are so interesting. In an interview with Nieman Lab’s Michael Andersen, he underlines the importance of showing people the results of their collaboration:

“Any time that you’re trying to get people to give you stuff, to do stuff for you, the most important thing is that people know that what they’re doing is having an effect. It’s kind of a fundamental tenant of social software. … If you’re not giving people the ‘I rock’ vibe, you’re not getting people to stick around.”

Willison says it was important to liken the site’s user experience to a video game. (Real-time?) results on the site’s home page offer measureable encouragement to participants — the score. And photos of the MP’s smiling face above each claim provide the narrative. The combination has been a key driver of user participation, Willison says.