The answer to that question actually should come in the form of another. Why would he ever have promised to do so in the first place? We now know that some of the tapes were embarrassing at best, and, at worst, devastating to his claims of innocence. The smart money said that savvy federal prosecutors were chomping at the bit to get him on the stand.
Still, week after week, in venue after venue, from reality shows to interview programs to the unexplainable crowds of trial tourists outside the Dirksen Federal Building, Blagojevich vowed we would see him on the stand. He did it again to a crowded elevator lobby Monday morning.
"Who here is going to testify?" he shouted. And he then raised his own hand.
"They proved what I said all along, that I did nothing illegal!" Blagojevich insisted in the lobby of the federal building after announcing his decision. "I sought the advice of my lawyers and my advisors. They proved I was on the phone with them brainstorming about ideas. Yes, they proved some of the ideas were stupid. But some of the ideas, were good."
Blagojevich and his attorneys simply said they expected a stronger case, and didn't want to dignify the one they finally saw, with a response.
"We think by putting him up there to answer anything, makes it seem as if the government was right," said defense lawyer Sam Adam Jr. "Did I get up there in my opening statement and tell them he was going to testify? Yes I did. Did I believe it at the time that I said that? Yes I did. Have things changed? They certainly have!"
"The law is clear," said defense lawyer Sam Adam Sr. "The burden of proof is on the government. They did not meet their burden. And I think the jury will see that."
And he may be right. And certainly some experts believe that actually putting the former governor on the stand far outweighed the risk faced by jilting a jury which had been promised a date with the star defendant.
But the Blagojevich team made a calculated decision not to put on any defense at all. Thus, if the jury has questions about the Children's Hospital deal, about the alleged roadbuilding shakedown, about Patti's alleged ghost job with Tony Rezko, and especially about the shenanigans revolving around Barack Obama's senate seat, those questions are going unanswered.
And what about the tapes?
"There is a good answer for that," Sam Adam Sr. declared. "And the answer is that the tapes that they played, are self explanatory."
That could be bad. Because many of those tapes seem to depict what are known as "acts in furtherance of the conspiracy," with Blagojevich giving his aides marching orders to follow up on his "brainstorming."
Number 19 was the tape where he told the people of Illinois what he thought of them (It goes without saying this is an all-Illinois jury).
And perhaps worst of all, tape number 93 may have been the closest this case had to a smoking gun. That's the one where Blagojevich talked about Jesse Jackson Jr.'s supporters offering "tangible support" up front for the Senate seat. On the tape, he tells his brother to extend the message that he'd better start seeing that support soon, if they really wanted to see their candidate appointed.
This is a gamble. And some gambles pay off. Many don't. Twelve people will make that determination, beginning on Monday.