IT TAKES ONE to know one.

A corrupt politician that is.

So, while I was puzzling over the obvious question in the Rod Blagojevich scandal - WHAT WAS HE THINKING? - I decided to ask one of our town's own crooked pols, Leland Beloff.

Beloff went from city councilman to felon in 1987, when he was convicted of conspiring with the mob to extort $1 million from one of our town's most upright citizens, developer Willard Rouse.

Rouse got wired by the feds and Beloff served six years in prison.

So I called Beloff to ask the questions that plague me whenever a pol takes a fall:

Why do it?

Why sacrifice a career of prominence, influence and public stature for money, especially when, as in Beloff's case, he didn't need it? He had money from family-owned nursing homes he's still running.

Why think you can get away with it when colleagues get hauled away in handcuffs all the time?

Sure, a million dollars was real money back when Beloff was shaking Rouse down.

But other Council members had been taken down by Abscam. And why didn't Beloff realize that Rouse was as likely to pay a bribe as Sister Mary Scullion - our town's version of Mother Teresa - would be to become a lap dancer?

Beloff gave me a simple answer:

He didn't do it.

. . . Oh!

I see.

He was busted by the feds, he said, because "I just got a little too powerful for my own good and I had some colorful friends.

"I didn't do anything wrong."

The colorful friends would be mob boss Nicky Scarfo and mafioso Nick Caramandi, both of whom were also convicted in the Rouse case.

But Beloff was nailed by Caramandi and another co-conspirator.

And he also pleaded guilty to forging absentee ballots in 1984 and was convicted of interfering with poll watchers in 1972.

I figured, his denial aside, he could still talk about the mind-set of a pol gone wrong.

He did.

"It's the power," said Beloff, now 66.

"You get some power, then you begin to think you have absolute power; it goes to your head.

"Everybody's bowing and scraping, it's a heady thing," he said.

"You don't have to wait in line anywhere anymore. The little everyday irritants in life that people put up with, you don't have to.

"You start feeling invincible after a while," he said.

As for Illinois Gov. Blagoj-evich, Beloff offered this assessment:

"I think he flipped his lid.

"The FBI has been investigating him for a number of years and he knows it," Beloff said.

"The first thing they do is bug your phone.

"He was talking on the phone about bribes being involved with a senatorial appointment. Would you do that if you were in your right mind?"

Beloff was slicker than that. Until his accomplices testified, the only evidence against him was a hand signal he delivered in a restaurant that an undercover FBI agent said acknowledged his role in the conspiracy.

Beloff is out of politics now, and he laments the reformist mind-set that has made wheeling and dealing illicit.

"In every legislative body, no matter what, you maximize your vote for your constituents," he said.

"You say I won't vote for your tax package unless I can have a bridge over Jones Creek. That's everyday give-and-take.

"Today it's against the law."

As Beloff said, the times may have changed.

But the corrupting nature of power, and the politicians who are driven to abuse it, obviously haven't.

Maybe lots of them get away with it, encouraging the rest.

And maybe, as a colleague of mine once theorized, high-profile political prosecutions that are intended to inhibit corruption wind up promoting it instead.

"Some people read about the latest bust and conclude that the whole system is rotten, that only a fool plays it straight," my colleague wrote in a 1992 magazine article.

Better a felon, in the minds of Rod Blagojevich and Leland Beloff, presumably, than a fool. *

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