Research 2000 had produced weekly political polls covering topics such as gubernatorial elections for the site for the past year and a half, said founder Markos Moulitsas. He stopped using the firm’s polls in June when Research 2000 scored poorly in polling blogger Nate Silver’s industry league table.

He was then approached by political consultant Mark Grebner, retired physicist Michael Weissman and wildlife researcher Jonathan Weissman – who questioned the quality of the surveys Research 2000 had carried out over that time.

The three were asked to write a report to back up their theory, which highlights statistical anomalies that they claim cast doubt on the reliability of the results.

Moulitsas alleges in a blog post that he had asked Research 2000 to provide its raw data for independent analysis, but the firm refused, and that it had yet to respond to the claims made against it by the statisticians.

“I hereby renounce any post we’ve written based exclusively on Research 2000 polling,” he wrote yesterday.

The matter has now been turned over to the Daily Kos’ legal team, Moulitsas said, which will be “filing suit within the next day or two”.

Research 2000’s president Del Ali told Research today “both parties are going to get this resolved pretty quick” but made no further comment.