Stations have held off changing their policies because of the uncertainty of an appeal, and because it so far affects only a limited area out West.
"We are monitoring the case closely and are concerned that lifting the ban on political advertising and public issue ads may undermine the trusted relationship we have with the American public and the objective environment we create for our programs," said Anne Bentley, spokeswoman for PBS.
National Public Radio said it will be up to individual stations to decide for themselves how to respond.
The case came to the court's 9th Circuit on appeal from the Minority Television Project, a corporation that operates the San Francisco television station KMTP-TV. While classified a public broadcaster, it gets no funding from the national Corporation for Public Broadcasting. A decade ago, KMPT-TV ran nearly 2,000 ads and was fined by the Federal Communications Commission. Their appeal challenged the advertising ban in general.
Product commercials are banned on the theory that public stations would reject educational programming in favor of more commercially popular fare to support the advertisers. The appeals court said, however, there's no evidence that political or public service messages would have the same impact.
Commercial stations in select markets have already picked up substantial revenue due to political advertising during the GOP presidential nomination fight, and in areas where the general election campaign is starting early.
There will only be more, particularly with the U.S. Supreme Court's Citizens United ruling easing restrictions on corporate campaign spending. The Kantar Media Campaign Media Analysis Group estimates as much as $3.3 billion could be spent on such advertising this year, up from $2.1 billion in 2008. Three-quarters of that is expected to be spent on local broadcast stations, Kantar said.
Stations that benefit most will be in presidential battleground states like Ohio, Colorado, Virginia, Iowa, Florida and North Carolina, said Ken Goldstein, chief of Kantar's campaign unit.
Politicians interested in advertising will have to consider whether public TV is the proper environment. Negative ads within genteel public programming would be "a little jarring," Goldstein said.
One California television station that is affected by the circuit court's ruling, KPBS in San Diego, has already said it would not take political ads even if given the opportunity.
"It's not our intention to make money off elections via political advertising," said Tom Karlo, the station's general manager. "Rather, KPBS will remain committed to educating the voters."
Some station operators fear there's a risk of upsetting viewers or listeners with political ads. "The fact that we can doesn't mean that we will or should," said Bill Davis, president of Southern California Public Radio, which operates three stations.
The advertising ban reinforces for listeners the fairness and balance that his stations strive for in news coverage, Davis said, adding that it also helps them believe the station is not going to be swayed by commercial considerations.
Some public media executives are concerned that the notion of accepting a political advertising windfall could even undermine their reason for being. Public stations frequently have to fend off critics who think the government shouldn't be in the business of funding them in the first place. The argument for public funding could crumble if there was substantial revenue coming in from political ads and this revenue is by its nature scattershot at best.
"I haven't spoken with many of my colleagues about this," Davis said. "But my hope is that they would have the good sense not to take these ads."