The stations, all ABC-owned, including KFSN Channel 30, removed the advertisements from airplay when lawyers working for the Yes on Proposition 5 campaign sent letters to station managers saying the commercial depicting the measure's harmful effects on the environment was "unequivocably and patently false."
Valari Staab, KFSN general manager and president, confirmed she temporarily pulled the ads after corporate lawyers said it would be the best immediate course of action.
"The last I heard was, we are not going to run the advertisement unless it gets better documented," she said Tuesday. "We've pulled it while we wait on substantiation of the ad."
The ad in question is a recently released 30-second television spot asserting that Proposition 5 could lead to widespread environmental degradation because tribes building casinos would be "exempt from environmental laws so they can dump sewage and toxic waste and pollute our air and water."
Using the example of a disputed casino project in Humboldt County, the advertisement says the Big Lagoon Rancheria ignored environmental law and local health officials when it began building its casino.
Lawyers paid by tribes supporting the ballot measure quickly fired off letters to station managers across California, saying that tribes remain subject to federal environmental and workplace laws, even though the measure would exempt them from parallel state statutes.
Daniel Pellissier, a spokesman for the Yes on 5 campaign, said he understands the need for political advocacy in the campaign. But, he added, this time the opposition went too far.
"We had to throw the flag and say 'no more,' " he said. The ad "is demonstrably untrue."
Gina Stassi, spokeswoman for No on Proposition 5 campaign said she hadn't heard that the advertisements were pulled.
Cathy Christian, a lawyer for the No on Proposition 5 campaign, maintained that the commercial should be run. In a response letter she sent to station managers, Christian asserted "the ad is completely accurate and has been fully researched and documented."
Christian said supporters of Proposition 5 are trying to divert attention from the ballot measure's flaws.
Proposition 5 is a November ballot measure that would change state law in California and allow tribes to keep the slot machines they now use. The campaign is setting records for spending with both sides pouring in more than $60 million to date.
The three stations pulled the advertisements after consulting corporate attorneys in New York. Lawyers there told the California stations to shelve the ads until the opposition campaign provides additional information supporting claims of widespread pollution waivers.
"The ads are under review at this point," said Julie Hoover, a spokeswoman for ABC. Hoover said the broadcast company expects a response from the No campaign within 24 hours.
Staab said when she told the No campaign that the station temporarily would shelve the ad, campaign workers quickly substituted another ad to run in its place. She said the station will continue to run other campaign ads.
It remained unclear late Tuesday whether any other stations would halt the ad. Under state and federal law, television stations do carry a measure of liability when convicted of knowingly running false election ads.