Chicago Alderman Edward Burke speaks during a city council meeting in Chicago, April 13, 2016 Photo: M. Spencer Green/AP

Jenner & Block's ties to the U.S. Attorney's Office for the Northern District of Illinois run long and deep. Now, the firm is defending one of the most high-profile Chicago politicians to be charged by that office.

The federal government Thursday charged powerful Chicago alderman Edward Burke with attempting to extort a business owner into using the alderman's personal property tax appeals firm. Burke is the longest-tenured alderman in Chicago history, first elected to the City Council in 1969. He faces a maximum sentence of 20 years in prison if convicted.

The Chicago Tribune said the latest headline-grabbing corruption charge of a local politician represented “arguably one of the biggest fish ever reeled in by the U.S. Attorney's Office.”

Plenty of Jenner & Block attorneys would be a good gauge of that. That includes Charles Sklarsky, a former assistant U.S. attorney in the Chicago office who represented Burke at a hearing Thursday in the Dirksen Federal Building and said Thursday his client did not commit extortion.

Sklarsky and a litany of Jenner partners including former chairman Anton Valukas and senior partner Thomas Sullivan were involved in perhaps the most well-known federal prosecution of Chicago government corruption: Operation Greylord. A Jenner & Block spokeswoman confirmed that Valukas is also representing Burke.

Sullivan launched that investigation as the former U.S. Attorney for the Northern District of Illinois, and Valukas, holding the same title, concluded the probe that led to roughly 90 convictions of judges, lawyers, deputy sheriffs, police officers and court clerks on a range of charges including conspiracy and bribery. That investigation, made public in 1983, showed that justice was at one time for sale in Chicago—judges were accepting bribes, often from Outfit-connected defendants.

The charge unveiled Thursday against Burke alleged that day-to-day business licenses were being held up in an effort to steer business toward Burke's long-time law firm, Klafter & Burke, which has helped high-profile clients, including President Donald Trump, reduce their property tax burdens.

“The transaction described in the complaint does not make out an extortion or an attempt to extort,” Sklarsky told reporters following Thursday's hearing. “We look forward to a prompt day in court to prove the innocence of Ald. Burke.”

Federal agents received a warrant from the chief judge of the U.S. District Court in Chicago to tap Burke's phone, the complaint says. They overheard conversations between Burke and an associate discussing plans to disrupt the remodeling work of a fast food restaurant and to ask the owners of that business to use Burke's law firm and to make contributions to at least one other Chicago politician.

The restaurant involved has been identified in local reports as a Burger King run by a franchisee who the complaint says operates some 162 restaurants in the area.

The complaint says representatives of the restaurant business met with Burke at a local country club to discuss their stalled renovation project. At the lunch meeting, Burke allegedly referenced his property tax firm. The business never hired the law firm.

“I was playing nice with 'em. Never got back,” Burke allegedly said in a conversation with a city employee apparently regarding the company's tax work.

The worker responded, “I'll play as hardball as I can.”

“Okay,” Burke replied, according to the complaint.

After a series of meetings, phone calls and emails, representatives of the business said Dec. 19, 2017, that they would be sending the tax appeals work to Burke's firm. The company received the permit it had been seeking on the same day, the complaint says.