A new TV documentary will reveal that a last-minute double-check of intelligence before the raid that killed Osama bin Laden cast fresh doubt on whether the al Qaida leader was really in the Pakistani compound where he was found.
The History Channel's Targeting Bin Laden special to be shown next Tuesday in the US, said president Barack Obama convened a special "red team" of terrorism experts to take a fresh look at the evidence.
That team had greater doubt that bin Laden was in the Abbottobad, Pakistan, home primarily because it did not believe he would take the risk of having as many visitors as he did.
Despite the new assessment, Mr Obama ordered the mission to proceed. Four days later on May 2 last year, a team of US Navy Seals successfully located and killed the terrorist leader behind the September 11 2001 attacks.
Mr Obama was interviewed two weeks ago for the special, which provides a tick-tock account of what went into the planning and execution of the raid. Other people interviewed for the special include national security adviser Tom Donilon, White House counter-terrorism adviser John Brennan and former CIA officials.
The "red team" had not been involved in the intelligence operation that searched for bin Laden or planned the raid. It was reviewing the evidence for the first time, History says in the special.
The team's assessment initially deflated policy makers, and only half of those planning the raid advised Mr Obama to proceed after hearing its report.
"At the end of the day only the president can weigh those risks," Mr Donilon told interviewers.
"Only the president can ask, 'What's in the nation's interest? What are the risks worth running here? What will we accomplish if this works? How will I deal with it if it doesn't work?' It was a quintessential presidential decision."