With the ugly news coming from the FBI’s investigation into state Sen. Ron Calderon, you’ve got to feel sorry for California politicians.

Not for Calderon, mind you. Remembering Joel Fox’s words in this space Thursday that the Montebello legislator is innocent until proven guilty, Calderon’s well-known penchant for testing the ethical edge had left plenty of folks thinking it was only a matter of time before something like this popped up.

No, it’s all the other honest politicians, in Sacramento and elsewhere, who are paying their own price for Calderon’s troubles.

Every time the FBI starts carting files and computers out of a legislator’s home or office (see Doolittle, former Rep. John), the FPPC dings someone for living the good life on campaign funds (see Florez, former state Sen. Dean) or slams the prison doors behind an out and out grifter (see Cunningham, former Rep. Duke), it becomes that much harder for voters to believe any officeholder in Sacramento, Washington or their own home town is on the up and up.

Just listen to disgruntled voters, who are increasingly convinced that the only reason people get into politics is as a shortcut to fame and fortune. A Gallup Poll taken last November asked people to rank professions based on their “honesty and ethical standards.”

Members of Congress finished next to last, ahead of car salespeople, but behind advertising guys and stockbrokers.

That has to be galling for the vast majority of council members, county supervisors, legislators and congressmen who got into politics because they wanted to make a difference and improve their city/county/state/country.

Every day they do their jobs, dealing with constituent complaints and problems, working with colleagues and pushing to pass legislation they’re convinced, rightly or wrongly, is best for the community.

It’s not easy and, yeah, every legislator faces tough ethical decisions and dicey situations. Even if you’re honest, the guy you’re dealing with may be a crook.

And when it comes to campaign contributions, if I give politician money because of the way she votes, that’s legal. But if I give her money to ensure what that vote will be, we’re all going to prison.

Like I said, it can be a thin line.

But there is a line and the vast majority of politicians knows it, accept it and don’t have to spend much time worrying about it.

And it doesn’t take a doctoral student of ethics to know that taking $88,000 to influence legislation, as Calderon is alleged to have done, is way, way on the wrong side of that line.

Calderon, upset that Assemblywoman Cristina Garcia of Bell Gardens and the mayors of a number of cities in his Senate district were calling on him to resign, said the effort was politically motivated and that “all politicians live in glass houses.”

He’s right about the glass house, since anyone who depends on the public to get elected knows that the same public is always watching to see if he should be unelected. That’s why, to toss out another metaphor/simile, a politician, like Caesar’s wife, must be above suspicion.

But Calderon wasn’t willing to stop there, saying instead that “what has happened to me could happen to anyone in public office.”

No it can’t, which is why the FBI isn’t serving search warrants on the other 119 members of the Legislature. But because the situation Calderon put himself into, his colleagues are sharing in the costs.

John Wildermuth is a longtime writer on California politics.