News that retiring Ald. Danny Solis, 25th Ward, has been secretly recording conversations with embattled Ald. Ed Burke, 14th Ward, shook City Hall on Wednesday.

Solis, the chairman of the City Council’s Zoning Committee, has long been viewed as an ally of both Burke and Mayor Rahm Emanuel. But the Chicago Sun-Times reported Wednesday morning that Solis has been wearing a wire for FBI investigators for the last two years.

Former federal prosecutors said that likely means that Solis’s conduct has also caught the attention of investigators.

“It’s likely that he was under some sort of investigation,” said Michael Monico, a former assistant U.S. attorney and now a partner at law firm Monico & Spevack. “Normally, a person would only agree to do this either if he is a victim of a crime or he is subject himself to investigation for some other offense.”

Gil Soffer agrees. He’s a former assistant U.S. attorney and now a managing partner at Katten Muchin Rosenman LLP.

“Generally speaking, if in a criminal case someone agrees to wear a wire to capture evidence on someone else – particularly someone who is not a political enemy or an enemy otherwise – the government has some leverage over him,” said Soffer.

For Soffer, the most important unanswered question is what else investigators may be looking into beyond the alleged attempted extortion detailed in the original complaint against Burke.

“If what we are hearing today is true and Ald. Solis has been engaged in consensual wiring for a long stretch of time, it raises the question, ‘About what?’” said Soffer. “Was there something else that the government was looking into? And also, was there anything that came from those recordings, because we are not seeing any reference to it in the complaint?”

Soffer said that he expects to see additional charges.

“All we are seeing in this complaint is an extortion charge. I would not be surprised in the indictment to see charges related to wire fraud or otherwise,” said Soffer. “It may relate to the same conduct but we don’t know if there is going to be other conduct that will be wrapped into an indictment.”

Both Monico and Soffer said that FBI investigators would have wanted a strong case before going public with their investigation.

“I would presume that they had substantial grounds since they had a search warrant for nine months,” said Monico. “Whatever reasons they had that they presented to a judge to allow them to conduct a search through a wiretap … there was presumably enough information there to presume to bring some kind of charges against him.”

And Soffer noted that in a so-called “heater case” like this involving a high-profile target investigators would be very careful about bringing charges.

“The consequences of going public are significant for the target of the investigation and his family,” said Soffer. “(Investigators) like to have their ducks lined up. That doesn’t mean they always prevail but generally speaking they are going to want to have everything ready before they go.”

Monico and Soffer join Carol Marin to discuss the latest developments in the Burke corruption probe.

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