Another critical misstep, Pitt believes, was Samuels' decision to send Arias a self-help book in jail.
"I think at best it was poor judgment and at worst it was an ethical breach of conduct. In a forensic context, when you are evaluating someone regardless of which side retains you, this is not a 'Kumbaya' experience. You are there as an independent expert to render diagnostic opinions that will help educate the jury. Your job is not to become buddies with the person you are examining."
On Wednesday during re-direct questioning by defense attorneys, Samuels insisted that he had not blurred any ethical boundaries and that the book was not meant as a form of therapy.
Another critical defense expert, Alyce LaViolette, is expected to take the stand next week and testify on issues of domestic violence, to give context to Arias' testimony about the alleged emotional and physical abuse that she says she endured with Alexander.
Pitt believes it will be difficult for the defense to turn things around.
"What the defense has been doing throughout is they have been putting the victim [Travis Alexander] on trial. And what they are doing is they are throwing up as much as they possibly can and hope that something sticks to keep Jodi Arias away from a couple of needles," he said.