A federal court filing this week came a tantalizing step closer to revealing the mystery of how former Ald. Edward R. Vrdolyak insinuated himself into one of the biggest legal fee jackpots in history.

At the same time, the new information from federal prosecutors left me thinking they still don’t quite have the goods on Fast Eddie and what may have been his sweetest score.

Prosecutors indicated for the first time Monday they have information Vrdolyak made cash payments exceeding $1 million to unnamed “individuals and entities” in connection with his own unexplained payday in the state’s $9.3 billion tobacco lawsuit settlement.

The implication was clear that authorities believe the $1 million-plus was a kickback from Vrdolyak to whoever conspired with him on the deal.

OPINION

Authorities say Vrdolyak and another lawyer have already been paid more than $10 million from the settlement even though they did no work. Court records have indicated he was due to collect even more.

The catch is that Vrdolyak has not been charged with anything so damning, and the only evidence offered of the cash kickback was an emailed threat from Daniel P. Soso, his now co-defendant, to make public the secret arrangement if Vrdolyak didn’t pay him his share of the fees.

The accusation drew a sharp response from Vrdolyak’s longtime defense lawyer and friend, Michael Monico, who called it “absurd and utterly false.”

“And if they had a shred of credible evidence of that, wouldn’t that have been in the indictment?” Monico told the Chicago Sun-Times’ Jon Seidel.

On that point, I have to say I find Monico to be at least partially persuasive.

If federal prosecutors had nailed down proof that Vrdolyak really did make the $1 million in cash payments (and to whom), I certainly would have expected them to make the case more strongly than with a reference to Soso’s email contained in a small-type footnote to Monday’s court filing.

Lawyers for both sides hinted months ago that there could be another, more wide-ranging indictment coming in the case, which is scheduled to go on trial in March. That hasn’t happened.

Soso’s lawyers have indicated they are working on a plea agreement with federal prosecutors.

I suppose one interpretation could be the footnote reference was a way of signaling prosecutors have a paper trail to support Soso’s account of what happened, if he chooses to cooperate with investigators.

I don’t doubt prosecutors can convict Vrdolyak of the less sexy tax charges he now faces.

What we all really want to know, though, is how Vrdolyak could have influenced the process by which the Illinois Attorney General’s office, then run by Republican Jim Ryan, chose its lawyers on the tobacco case. One of those lawyers, Seattle’s Steve Berman, made the secret deal to pay Vrdolyak and Soso.

Prosecutors have all but cleared Ryan of wrongdoing in the case, but somebody like Vrdolyak could have found other pressure points either inside or outside Ryan’s office.

As I was packing up my office at work this week for our latest move, I ran across a piece of Vrdolyak memorabilia.

It’s a memo pad from his last campaign. Printed at the top is:

“ELECT for MAYOR

VRDOLYAK IN 89

Punch 15”

Vrdolyak lost badly to Richard M. Daley in that 1989 election, which essentially marked the end of his public life in politics.

Yet he remained a force behind-the-scenes, doing deals, until he finally got jammed up for a crooked one with businessman Stuart Levine, a friend of Jim Ryan.

By the time Vrdolyak is scheduled to go on trial, he will have turned 80.

I was thinking that I never grow tired of following his exploits. He must feel the same way about keeping all those secrets.