In All Seriousness.
When Shakir says X the intelligence officers do not dismiss X as false nor accept X as true. They file it away and see how X fits in with other interrogations and other evidence. Only then do they come to judge if X is true or false or somewhere in between. At the most X (until confirmed) will serve to shape future investigations or interrogation sessions with Shakir and others. Rarely will they immediately run out and act on X without other evidence.
A Star Trek - Next Generation episode demonstrates the perils of diving head first based into action based on inadequate interrogations. The Enterprise is patrolling near the Romulan-Federation neutral zone when a Romulan ship comes charging through the neutral zone being chased and fired upon by other Romulan ships, the Enterprise turns away the pursuing Romulan ships and captures the Romulan in the first ship. It turns out the Romulan on the fleeing ship is a high ranking Romulan commander defecting with vital information. He tells his interrogators the Romulan Empire is starting to implement a plan to attack the Federation and if a nearby base is not destroyed soon it will be too late to stop the invasion.
The Captain is not convinced by the defectors story because the defector will not give up tactical information about the Romulan fleet but eventually, Picard talks the defector into giving up that information. The Enterprise goes into the neutral zone and when they arrive at the scene of the supposed base there is nothing but Romulan ships waiting to attack the Enterprise. The Romulan defector was fed bad information by his superiors (who suspected him disloyal) who then went to the Federation. The Romulans were going to use the Enterprise's incursion as an excuse to start a real war but as it turns out the Enterprise summoned some backup with saved the day. The drama played out in t he episode is a situation where everyone believes (or is brought to believe) they are in a do or die situation, if the Enterprise crew would have had the luxury of having other Romulans to interrogate then they may have uncovered the ruse or at least have had more doubt cast on the story of the defector.
Sometime ago on the Discovery Channel (or History Channel or similar) had a show about modern interrogation techniques. They had a gang of people who were given a story they were not supposed to reveal to anyone. Then at a time and place unknown to them they were captured and brought to an interrogation facility. The goal of the interrogators was to discover the story they were told.
The techniques used by the interrogators were good-cop/bad-cop, discomfort (most often high AC with little or no clothes), stress positions, and sleep deprivation. All but one of the interogatees talked to one extent or another, some a little bit some a lot. No one person told the whole story. I can not recall if anyone tried to lie to the interrogators (I think some did and if they did, it did not work). In the end the interrogators were able to piece the entire story together.
The press and some out there keep talking about the unreliability of "tortured testimony" while they keep ratcheting down the definition of torture. Pretty soon they will want us to read terrorists their Miranda rights and from there the mere reading of Miranda rights will come to mean torture.
The press though has its own problems. From the reporting last year it appears no matter how dubious the source as long as the source confirms their prejudices the story must be true. For example the Koran story was essentially based on a single source, but it confirmed what Newsweak wanted to believe and so they ran with it. Dan Rather's memo story same thing happened, they wanted to believe it so bad they ignored warnings from document experts and went ahead with it. One is tempted to say physician heal thyself.