During his closing argument to jurors, defense attorney Mark Geragos asked jurors to keep one question in mind. If the government prosecutors believed Brent Wilkes had plied Congressman Randy “Duke” Cunningham with more than $600,00 in bribes, why didn’t they put the ex-honorable gentleman on the witness stand?

It’s a good question. As the jury enters its third full day of deliberations, they may be wondering the same thing, and it remains to be seen whether keeping Cunningham off the stand will hurt the government’s case.

In his closing argument, Geragos told jurors the government didn’t call Duke because he would never, ever admit that Brent Wilkes’ contracting work was bad for the country. Prosecutor Jason Forge countered that in rebuttal by saying that he didn’t want to call the most corrupt congressman in history and ask jurors to rely on his testimony.

So why didn’t Geragos call Cunningham ? Geragos said the government had the burden of proof. When I reminded him that he had told jurors he would call Duke, Geragos replied that Wilkes was a better witness. It’s not too hard to believe that he was worried that Duke would admit that Wilkes had bribed him. And that would be something no amount of brutal cross-examination could undo. You might as well send the jury out right then.

The statements from both sides leave a bit to be desired; something’s missing here. We’ll find out someday, but for now, it’s clear that both prosecutors and the defense felt there was more harm than good in calling the Duke to testify. Was anybody really sure what he would say? Cunningham has a history of instability and, more importantly, he’s not the smartest fellow, so there’s no telling what someone as smart as Geragos could get Cunningham to concede. Just look at what he did to other, more intelligent witnesses. And sitting next to Geragos at the defense table was a man who knew Duke better than almost anyone.

In the final analysis, it bears noting that for both sides the least reliable witness wasn’t Mitch Wade, the double-crossing greedy cheat who admitted paying Cunningham $2 million in bribes. Nor was it Brent Wilkes, who is awaiting to hear whether jurors thought he was lying on the witness stand and will convict of bribery, money laundering, fraud and conspiracy.

No, the most unreliable witness happened to be one of the most highly decorated pilots of the Vietnam War, an eight-term congressman from San Diego who never lost an election, the former member of the powerful Defense Appropriations subcommittee, Randy “Duke” Cunningham.