A “PSYCHOTIC” boyfriend strangled and stabbed his partner because he believed she had been possessed by the devil, a court heard.
In the weeks before he killed Gemma Finnigan, 24, her live-in boyfriend Daniel Johnson, 32, had developed a bizarre interest in conspiracy theories and aliens, and even his own sister described him having a look of “pure evil”.
Miss Finnigan’s body was found in the bedroom at their home at Church View, Boldon Colliery, on September 13 last year, after Johnson had been found wandering around his old school in Kenton, Newcastle, shirtless and acting strange.
Police had forced their way into the address after Miss Finnigan could not be contacted.
At the police station after his arrest, Johnson switched between acting like a dog on the floor of his cell to threatening to cut someone’s throat.
Prosecutor Jamie Hill QC told Newcastle Crown Court: “He actually killed Gemma Finnigan believing that she had been possessed either by the devil or an evil spirit. That appears to be the conclusion.
“Against that background, I anticipate doctors will say if that is the case, he did not know what he was doing was wrong, he thought he was killing the devil, protecting her and himself at the time.
“In those circumstances, that would mean he was in a delusional state and insane in law.”
Johnson, who is currently being held at Rampton secure hospital in Nottinghamshire, and has waived his right to attend his trial, denies murder.
Mr Hill told jurors Johnson admits he carried out the killing, but pleads that he is not guilty but insane.
Mr Hill said three experts have concluded Johnson was suffering paranoid schizophrenia and was psychotic at the time of the killing.
The court heard prosecutors do not invite a verdict of guilty to murder in the case and jurors have been advised they will be asked to consider the alternatives of guilty to manslaughter on the grounds of diminished responsibility, and not guilty but insane.
Mr Hill told jurors Miss Finnigan had met Johnson in 2008 while he was on day release from an open prison following a “substantial” sentence.
The couple had lived together at the flat in Boldon for three years when Miss Finnigan was killed.
Mr Hill said Johnson had a minor psychiatric background and had been treated for mild depression in 2010 and 2011, but there was nothing to hint at the “calamitous deterioration” which took place.
The court heard it was about two weeks before the killing, Miss Finnigan had grown concerned about Johnson’s behaviour and had even booked him in to see a doctor the day before her death, but he had refused to go.
Mr Hill said: “Gemma started reporting to family members that Daniel Johnson had become interested firstly in American conspiracy theories, then had started staying up at night, bought a telescope and was looking at the stars.
“There were suggestions he was concerned about extra terrestrial aliens. She would find him sometimes, in the very early hours of the morning, kneeling by the bed, praying.
“He had started to say strange things, suggesting he was in possession of special knowledge. His behaviour became increasingly bizarre.
“His sister, who saw him two days before he killed Gemma, described him having a look of pure evil on his face.”
The court heard on the morning of September 13, a neighbour heard what must have been the fatal attack, where Miss Finnigan was strangled and then stabbed, at around 3.30-4am.
At 7.30 that morning, he was found inside Kenton school and was arrested. After family and friends heard of his arrest, concern for Miss Flannigan grew until the police forced entry to the flat and found her body.
The trial continues.