NEW Now you can listen to Fox News articles! A disturbing video shown in a Texas courtroom depicts the former FedEx driver, who admitted guilt in the killing of 7-year-old Athena Strand, switching between personalities—while his defense team pleads for sparing his life citing mental health challenges. Tanner Horner, 34, entered his guilty plea to the abduction and murder of Athena right before his trial was scheduled to start in Fort Worth this week. A jury will determine whether he receives a life sentence or the death penalty. Jurors have viewed several days of body camera footage and police interrogation videos showing Horner’s interactions with authorities after his arrest, as they deliberate on the death penalty. Defense attorney Lindsay Thompson has sought to portray Horner sympathetically by disclosing his autism diagnosis, brain damage, mental illness, and severe lead exposure. BODYCAM FOOTAGE REVEALS ATHENA STRAND’S KILLER, FEDEX DRIVER, SWITCH PERSONAS; CLAIMS DITCHING GIRL’S CLOTHES WAS ‘FUNNY’. In court on Thursday, haunting body camera footage showed Horner instructing officers to talk to his alter ego, whom he called “Zero.” In the video clip, the officer asked, “Hey Zero, when you took her, was she wearing a jacket or anything?” referring to Athena. Horner, responding as Zero, said, “No jacket, no shoes.” This sudden apparent personality shift occurred during Horner’s encounter with police, alarming Dr. Carole Lieberman, a forensic psychiatrist and expert trial witness. ATHENA STRAND’S KILLER FEDEX DRIVER TOLD POLICE HE ‘KIND OF TOSSED’ 7-YEAR-OLD’S BODY INTO WOODS, VIDEO SHOWS. The most striking aspect from a criminal profiling viewpoint is the multiple personas Horner has displayed in various situations, Lieberman told Fox News Digital. “He has appeared completely sane at times, yet he also claims to have a separate identity or alter ego, suggesting he may have been manipulative—like a malingerer or psychopath—on other occasions.” VIDEO: Athena Strand’s murderer admits he ‘just kind of tossed her’ into the woods. As the body camera footage kept rolling, jurors heard officials speak directly to Zero after discovering that the alter ego seemed more “helpful.”