The cell phone expert, whose evidence made up a large part of the state's case against Adnan Syed, has signed an affidavit that states that he no longer stands behind his testimony.

In a blog post on the Serial website, Sarah Koenig outlined that Abraham Waranowitz's evidence was not the most interesting part of the case (in fact she describes it as a technical and "soporific") but that it was "used to corroborate Jay’s story about what happened. So Waranowitz’s interpretation of those cell records underpinned the state’s entire case against Adnan".

His evidence helped to place Adnan, together with Jay, at Leakin Park, the place in Baltimore where the body was buried and subsequently discovered by the police. 

However, he claims that there was a "critical" piece of evidence attached to the phone records that the police were given, but he never saw it. It states: "outgoing calls only are reliable for location status. Any incoming calls will NOT be considered reliable information for location". 

In the affidavit, which he signed earlier this month, he stated that he was presented with a document "which I was viewing for the first time — referred to as State’s Exhibit 31. I remember viewing one page of the document. Since this appeared to have ordinary AT&T cell site data on it, I accepted it as it was presented", but that had he seen the critical document that was missing, "I would not have affirmed the interpretation of a phone's possible geographical location until I could ascertain the reasons and details for the disclaimer".

As Koenig points out, what this means is that one of the state's key witnesses is saying that his own testimony is potentially unreliable.

The affidavit forms part of Adnan's case for ineffective assistance of counsel during his case, which has been taken up by his attorney C. Justin Brown, and will be part of a claim that the State "knowingly withheld exculpatory evidence at trial". 

Via Serial