I’m starting to understand why senator Roland Burris keeps saying he didn’t do anything wrong as if he actually believes it.

Just a little while ago U.S. Attorney Patrick Fitzgerald stood before reporters and offered details of the latest federal indictment of a local politician. This time it was west-side alderman Isaac Carothers being placed squarely on the hot seat and accused of bribery.

“I think I’ll start my story by saying, ‘Federal authorities confirmed today that Arenda Troutman was right: most aldermen are hos,’” said the reporter sitting next to me.

The feds didn’t put it in those exact terms, but they did allege that Carothers helped developer Calvin Boender negotiate with the city for a zoning change that helped Boender make at least $3 million selling portions of an old west-side rail yard. In return, Boender allegedly set Carothers up with White Sox playoff tickets, meals, campaign contributions, and $40,000 worth of improvements to his house that included fresh paint, new windows and doors, and a new air-conditioning system.

Carothers may bitch and moan about the Daley administration from time to time, and he’s great at asking pointed questions during City Council hearings. But he’s fundamentally a mayoral loyalist who as chair of the council’s police and fire committee has helped thwart any serious legislative oversight of the police department.

He was born into bare-knuckles west side politics—his grandfather was a ward committeeman and his father was an alderman who eventually was convicted of accepting bribes. And while the west side isn’t the machine powerhouse it once was, Carothers still has a ward organization comprised in part of government workers, and it’s delivered for him and for neighboring alderman Emma Mitts.

Among the favors allegedly given to Carothers in return for his zoning help were donations to Carothers and to “Candidate A”—described as a Carothers relative who ran for Congress in 2004. That would be his aunt Anita Rivkin-Carothers. The problem with the contributions, according to the feds, was that Boender allegedly had somebody else make them on his behalf so he could conceal the source: “Defendant Boender directed an employee of [his company] to make a $1,500 donation to the New 29th Ward Democratic Organization and reimbursed that employee for that contribution,” the indictment says.

Which brings me back to Senator Burris, who was recorded saying that he’d love to help former Governor Blagojevich with some money but had the good sense to suspect it would look bad while he was seeking a Senate appointment. “If I do that I guarantee you that that will get out … and then Rod and I both gonna catch hell.”

Maybe, then, he could do some fund-raising a less direct way: “And my law partner, we were gonna try to do something at the law firm,” Burris said. “I might be able to do this in the name of Tim Wright.”

Fitzgerald thundered today against “straw donations,” which are against the law, even by the otherwise relaxed standards of Illinois. What he declined to talk about is how common this kind of arrangement is.

So I’ll say it: it’s really common. Just like offering gifts for a zoning change or a business license, or even as a chit that might have to be called in sometime later, it’s the way things have been done around here for ages.

Anyone tempted to give or take a bribe, “even if it’s $5, should take notice today,” Fitzgerald said, “because the consequences are serious.”

That’s why it’s best to try to do the right and wise thing: keep your name out of it and don’t get caught.