Goetz and Humphrey homed in on June 16, 2008, and quickly discovered the misspelled search for "fool-proof suffication."

"It shows you a state of mind that was present on the actual afternoon it appears the child had died," Humphrey said. "So I think it would be important regardless of who it was making the searches, but in this case it's certainly important that it appears to be Casey Anthony herself."

What they found astounded them and left at least one crucial question unanswered: How could prosecutors have not used this at trial?

Searching for that answer, they turned the browser history files over to Local 6.

After authenticating the records and interviewing defense, prosecution and Sheriff’s Office sources, it became clear: two citizen-investigators accomplished in less than three hours what an army of Orange County investigators and prosecutors failed to do in three years: uncover in detail what Casey Anthony was doing online the day Caylee died.

Of course, unbeknownst to investigators and prosecutors, it was also uncovered many months earlier by someone else: Jose Baez.

The defense: George did it

"I don't understand how no one ever knew about this evidence," Baez told Local 6. "We were keeping it close to the vest and ready to counterpunch in the trial, and it never came out."

The defense's still-cocked counterpunch: George Anthony did it.

After Baez's computer expert found the June 16 search for “foolproof suffocation" (Baez said he cannot reveal exactly when that was), Baez said he suspected the state knew about it, too, and was going to surprise the defense with it at trial.

In his revealing book, "Presumed Guilty," Baez accused investigators of "pulling a fast one" by concealing the vast majority of the June 16 computer history from the defense. Mostly vague references to that day's activity and some images were included in the documents turned over to the defense by the state in the discovery process.

What our reporting confirmed happened never occurred to Baez: that, in this small but crucial area, the investigation was so lacking it failed to discover the search.

But if they had, Baez said, he was ready.

"It turned out to be a huge bombshell that we thought would be the knockout blow in this case," Baez said, anticipating the defense would knock out the state by arguing the search showed George Anthony contemplating suicide, not Casey Anthony researching how to kill.

"It appears suicide had long been on George's mind," Baez wrote in “Presumed Guilty,” noting George Anthony attempted suicide in January 2009.

Asked by Local 6 if the foolproof suffocation search and visit to the site discussing ways to kill showed consciousness of guilt, Baez said, "To me, it tells me someone's feeling very guilty of something and is considering suicide. To be considering suicide the day Caylee died was huge for us."

Asked if that meant he believed whoever did that search was responsible for Caylee's death, Baez said, "I think 'responsible' is too strong a word."

His book explores various scenarios, all pointing to George Anthony.

But, in doing so, Baez relies on several assumptions that are refuted by evidence developed and confirmed by Humphrey, Goetz and Local 6.

The defense's flawed timeline

As part of the book's "concrete proof" it was George Anthony and not Casey Anthony doing the foolproof suffocation search that afternoon, Baez notes correctly it was immediately preceded by a login to an AOL Instant Messenger account.

"Right after someone logged in to instant messenger," Baez writes in his book, "the first search was to Google" for foolproof suffocation.

That much is confirmed by the evidence. But then Baez errs in writing, "George had an AOL Instant Messenger account. Casey didn't."

In fact, Baez now concedes, Casey Anthony did have such an account, known as AIM.

And Goetz recovered encrypted data showing it was Casey's Anthony’s AIM account screen name – casey o marie – and not George Anthony’s that logged in just before the foolproof suffocation search.