[6:50 p.m. update: added information from the networks' attorney.]

ABC, CBS, NBC, Fox News, CNN and Associated Press are suing Secretary of State Mark Ritchie and Attorney General Lori Swanson over a new law pushing exit pollers further from the state's polling places.

In a complaint (PDF) filed today in federal court, the nation's media biggies say the law — the last of its kind nationally — unconstitutionally impairs their ability to conduct accurate exit polls.

The state has long had a 100-foot "exclusion zone" open only to voters and election officials. A change, passed this spring, now measures the 100-foot circle from a polling place's front door instead of the inside room where voting takes place.

The result, says the filing, "substantially expand[s] the exclusion zone" — violating the First and 14th Amendments.

The networks' attorney, Susan Buckley says Minnesota's status as a possible swing state didn't prompt the suit. "Frankly, you're the last one left standing," she says.

Since 2004, federal courts have thrown out 100-foot restrictions in South Dakota, Nevada, Florida and Ohio, Buckley says.

The media companies want a U.S. District Court judge to block the state from enforcing an exclusion zone for 2008, then seek a permanent injunction to have the zones prohibited.

Even if the 100-foot restriction goes away, Buckley says existing state law would keep exit pollster out of the polling place.

The complaint make the case that ever-widening restrictions impermissibly harm newsgathering:

"As a polling reporter moves farther and farther away from the polling place, the likelihood of a voter getting into his or her car and driving away, or of melding into a crowd of non-voters, increases.

"Second, as distance increases, it becomes harder to discern those who are voters from those who are not.

"Third, as distance increases, the statistical reliability of the sample itself decreases because it becomes impossible to interview in the scientifically selected pattern (e.g. every fourth voter, every fifth voter, etc.)."

The suit names Ritchie and Swanson in their official capacity administering Minnesota law. The complaint states that the Secretary of State's office told media representatives earlier this month that exit pollsters would be banned from the wider zone.

Contacted Monday afternoon, Ritchie said neither his office nor Swanson's had received a copy of the complaint. "It's impossible to comment on something I haven't seen," Ritchie said. "We have no knowledge of this. We haven't seen any sign of this whatsoever."

By the way, one plaintiff's attorney is John Borger, husband of MinnPost contributor Judy Borger. I received a copy of the complaint from someone unaffiliated with either side.