A lawsuit filed Thursday against Avvo.com aims directly at the Seattle startup's distinctive feature — a system of rating attorneys across the country on a scale of one to 10.

The plaintiffs, John Henry Browne and Alan Wenokur, are practicing lawyers in Seattle who called the system unfair.

They think their ratings, 5.2 and 6.5, respectively, were uncharacteristic of their experience, industry recognition and professional conduct.

The suit, which is seeking class-action status, was filed in U.S. District Court in Seattle by Steve Berman, a Seattle attorney who has handled high-profile class-action cases and is a partner at Hagens Berman Sobol Shapiro.

The defendants named in the suit include Avvo and its chief executive, Mark Britton, former general counsel at Expedia.

Berman said the rating of Browne, a criminal defense attorney in Washington for 35 years, was hurt because Browne had been sanctioned by a state disciplinary authority.

He said a couple of potential clients who visited Browne's office last week said they would get another attorney because of the average rating.

The suit alleges the ratings violate laws against unfair competition and deceptive acts as outlined in the Washington Consumer Protection Act. Berman said it seeks an injunction to shut down the site or get it modified.

Britton said Avvo, a free site launched June 5, aims to give consumers information that is otherwise difficult to find. It includes data about lawyers in nine states and the District of Columbia, with intentions to add more.

"We built Avvo to give consumers the information and guidance they need to choose the right lawyer," Britton said.

"As long as we continue to focus on the consumer, we should be in good shape," he said.

Berman says the site is unreliable. He cited an example of how a lawyer was able to raise his rating after entering information about an award he won during a softball game — something unrelated to practicing law.

Britton said that could be possible. If an award is added to the site that does not fit into a number of pre-determined areas, it can affect the rating but will be flagged.

An Avvo employee later goes through the site and checks to see if the award is meaningful. In the case of the softball award, Britton said the lawyer would get points at first, then lose them if the employee later deemed it inappropriate.

"We knew what we were doing was something new, and it would take some time for people to get their arms around it, but we were not expecting this visceral of a reaction," he said.

Tricia Duryee: 206-464-3283 or tduryee@seattletimes.com