An Australian man accused of murdering a Thai teenager and attempting to flee the country has been described as an "insightless, gormless psychopath" by a forensic psychologist analyzing his police interview. Simon Peter Carman, 45, faces charges of murder, concealing a body, and offenses relating to a minor in connection with the death of 17-year-old Tunchanok Donhomla.

Police allege Carman killed Ms. Donhomla in his condominium in Pattaya after an argument over payment. The pair reportedly met early Thursday morning on Beach Road. Ms. Donhomla's parents, who have demanded the death penalty for Carman, stated she had only recently arrived in Pattaya and had gone with a friend.

Forensic psychologist Tim Watson-Munro characterized Carman's recorded message to the victim's parents—where he stated, "I feel bad for what happened to your daughter. It was out of my control. I know you'll be very sad, upset, same, same me. It shouldn't happen, and I hope you're OK. I know you're not, but I hope, and please tell other girls…to be careful"—as simplistic and potentially "self-serving."

"Anyone who's [allegedly] killed someone saying that - 'I feel bad and I hope everyone's all right' - it's like, 'Can we go back to the footy'," Watson-Munro told the Daily Mail. He added that Carman's warning to other girls could be interpreted as a "consciousness of guilt statement without declaring it."

Carman, who was reportedly living in Thailand for eight months working as a handyman and keeping a low profile, denies murder. He allegedly told police he acted in self-defense after Ms. Donhomla attacked him with a knife, a claim Watson-Munro called "far-fetched."

Investigators allege that after the murder, Carman placed Ms. Donhomla's naked body into a suitcase and dumped it near railway tracks, a short distance from his condominium. CCTV footage reportedly shows Carman wheeling a suitcase from his hotel before strapping it to a motorbike. The suitcase was later found containing Ms. Donhomla's belongings.

Carman was arrested at Bangkok's Suvarnabhumi Airport shortly before he was scheduled to board a flight to Perth. He reportedly told police that scratches and bruises on his neck and arms were from spiders. There have been unconfirmed reports that Carman may have had a brain tumor, which was a reason he was living in Thailand.

In Thailand, a murder conviction can carry the death penalty. Ms. Donhomla's stepmother has stated she wants Carman executed. Ms. Donhomla's father expressed deep sadness over his daughter's death.