By Pat Loeb

PHILADELPHIA (CBS) – Lawyers for alleged child abuser and former Penn State football coach Jerry Sandusky begin their defense this week. They plan to present evidence that Sandusky has a personality disorder.

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The defense has received permission to call an expert witness to testify that some of the evidence against Sandusky could be attributed to his suffering from “histrionic personality disorder,” rather than the criminal intent prosecutors have ascribed to it.

This includes letters Sandusky wrote to the young men who have testified in court that he abused them. Defense attorneys say the expert will show the letters were not intended to “groom” recipients, but motivated by the needs of “a psyche belabored by the needs of” the disorder.

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The disorder, according to educational psychologist Chuck Williams, who has no involvement in the case, is marked by a need for attention and approval.

“Being easily influenced by other people, overly dramatic and emotional, overly sensitive to criticism or disapproval, blaming failure and disappointment on others and constantly seeking reassurance.”

Prosecutors are expected to present a rebuttal witness.

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