CHICAGO (AP) - Despite vowing for months that he would speak directly to jurors, an influential Cook County commissioner told a federal judge on Wednesday he would not be taking the stand at his tax-evasion trial.

A calm but somber William Beavers walked to a courtroom podium, adjusted his tan suit coat and looked up at U.S. District Judge James Zagel, who asked if it was the Chicago Democrat's decision not to testify.

"That's a decision I made your honor," Beavers responded in his deep, booming voice.

The 78-year-old Beavers indicated several times that he had difficulty hearing as he stood several yards from the judge's bench. At one point, he told Zagel, "Can you speak up a little so I can hear you?"

Beavers pleaded not guilty to four tax charges, including allegations he failed to report campaign cash he used for gambling as income on his federal tax returns. Each count carries a maximum three-year prison term.

Beavers' announcement that he wouldn't testify came just before the defense rested. The defense's case lasted half a day and involved just one witness, an accountant who said tax laws involve a variety of interpretations.

Closing arguments were set for Thursday morning.

The one-week tax trial has revolved around otherwise drying accounting issues. But the possibility that tough-talking, rhetorically gifted Beavers could speak in court had attracted wide media attention.

Zagel ruled before testimony started last week that only one person, Beavers himself, could tell jurors he paid overdue taxes and that any mistakes on his returns were unintentional. That seemed to increase the chances he would testify.

And the former Chicago police officer and alderman, who once bragged about his influence by calling himself a "hog with big nuts," pledged repeatedly in public that he would take the stand.

"I've got to tell what these people are all about," he told reporters last week, referring to prosecutors. "What they're really all about is that they tell some tall tales. ... I gotta straighten them out."

Beavers immediately assumed an air of defiance after his 2012 indictment, going as far as accusing the then-U.S. attorney of using "Gestapo-type tactics" to prosecute him. And that, too, suggested he might testify.

But testifying would have involved enormous risks, subjecting Beavers to a blistering and potentially damaging cross-examination by prosecutors.

Another prominent defendant tried in Zagel's courtroom, former Illinois Gov. Rod Blagojevich, also insisted before his first trial that he would testify. But he chose not to in that initial trial, which ended with a hung jury.

Blagojevich did testify at his retrial and was convicted on multiple corruption counts; he's now serving a 14-year prison term in Colorado.

Blagojevich's lead attorney at his first trial, Sam Adam Jr., is delivering the closing for Beavers on Thursday. Carrie Hamilton, one of the trial attorneys for the government at both of Blagojevich's trials, will close for the prosecution.