So how is he supposed to know any better? Was he supposed to watch Nancy Grace first so he could properly be biased? You people are only looking at this from your point of view. He was a professional, hired to interview someone he doesn't know. He gave an honest assessment of the person after the interview. Simple as that. It's the lawyer's job to discredit Casey's statements, not the doctor's. He was doing his job.
There are any number of psychiatric/psychological professionals on this forum and others (not to mention any of us simply noticing her behavior recorded on film from Day 31) that have suspected she has a personality disorder. Those personality tests are not definitive, they can sometimes flag personality disorders but diagnosis is not immediate and many professionals will deliberate or require many many sessions before they specify a diagnosis. Those doctors should have spent a lot more time analyzing her behavior and affect and not simply reporting what she said as if it were true. It's also true that some professionals just are not very good diagnosticians when it comes to subjective evaluations.
IIRC, both of them met with her early on in jail and said she was fine (which is different from having a diagnosable mental illness that could have been used to cop an insanity plea). The DT dredged them up later, probably because they knew their initial work was a bit cursory. When one of the doctors found out he was basically going to be used as a professional mouthpiece for hearsay in court, he refused to testify. The state saw through this rather transparent ploy to avoid putting KC on the stand with her testimony subject to cross and the whole thing fizzled out. Neither of these men were willing to put their reputations on the line to say these things in open court.
A lot of stuff she said in her interviews should have been further analyzed. The fact that she was also "unusually cheerful" during her initial jailhouse interviews - when Caylee was first reported "missing" was a huge red flag, not to mention her incessant preoccupation with herself and her person, the Lady Macbeth hand-rubbing and other physical tics that drove us nuts during all those hearings.
I think what is rankling is that when most people in the general public, not to mention body language experts and other psychological professionals, can immediately see there is something wrong with her (something that the defense had to cover up as "ugly coping") - and her behavior and demeanor and affect are extremely similar to other well-known deviant/sociopath/murderers like Diane Downs, Drew Peterson and Scott Peterson - it would be circumspect and professional to have withheld their opinion pending a more thorough analysis or investigation, particularly since this person was a defendant in a murder trial and their testimony could be critical. This is not a matter of being unduly influenced by the media - anyone who heard her talk on that 911 call got chills from her lack of affect regarding Caylee. Any doctor who didn't take into consideration all of the available evidence of her well-documented behavior over a three-year period was simply doing a sloppy job, imo. If these doctors missed red flags that many others here in the field saw immediately, and were so apparent they stand out to absolutely everyone, then they need to be able to defend their diagnosis with a bit more detail and clarity than they did.
I think their "work" was pretty much on the same level as Dr. Spitz who flapped about in court because a skull was not cracked open and other irrelevant twaddle and gave the general impression of someone whose faculties had all but disappeared.
They were simply being paid to listen to the defendant's lies and to testify in court as if they were true. Sometimes I wish they had been on the stand because I think Linda could have eviscerated their testimony in a few minutes. (Which would have certainly entertained us all, but would have meant nothing apparently to a jury whose members were too bored to even review the evidence before they rushed to verdict).