While awaiting trial in Long Bay's remand section Archie had nearly killed another prisoner with his slops bucket. The only way to calm Archie down was with sedatives. At first, normal doses had no effect. So prison doctors kept increasing the dosage until they took effect. His daily dosage of 1500 milligrams of the potent tranquilliser Largactil was almost four times the normal dose of 400 milligrams. Prison psychiatrists agreed that McCafferty's incredible tolerance to massive doses of tranquillisers was in itself evidence that he was insane.
At the trial, three psychiatrists gave their opinions of Archie's mental state. Dr William Metcalf, a Macquarie Street specialist, was called to give evidence on behalf of the defence. He said that in his opinion McCafferty was insane at the time of the killings because he did not know what he was doing was wrong. Dr Metcalf pointed out that Archie was mentally ill and his mind was not in tune with reality. He was a paranoid schizophrenic at the time of the killings.
A completely different opinion was given by the prosecution's psychiatric adviser, Dr Oscar Schmalzbach, also a Macquarie Street specialist and consultant psychiatrist to the state government. Dr Schmalzbach said; "In my view McCafferty knew at the time that what he was doing was wrong. He may have had an isolated schizophrenic reaction at the time of the second killing but this did not make him a paranoid schizophrenic. Such an illness does not exist one day and disappear another day and come back the third day."
A third psychiatrist who examined McCafferty after the killings did not give evidence. He took the middle view that McCafferty was insane but he knew what he was doing at the time of the killings.
Although they could not agree on Archie's sanity, the three psychiatrists were united in the opinion that, no matter what, Archie McCafferty could never again be set free. They all agreed that he was an extreme danger to the community.
Then it was Archie's turn and the hushed courtroom was captivated as he told of the voice from the grave and how he had been told that seven must die if he wanted to see his son again. He maintained that he was completely insane at the time of the murders. The press lapped it up and Archie didn't disappoint them. At last he was getting the recognition that he so desperately craved. Even if he had to kill three people to get it. And in true trouper fashion, Archie saved the best bit until last, his statement, which he read from the dock:
"Your Honour and gentlemen of the jury. Firstly, I would like to say that at the time of these crimes I was completely insane. The reason why I done this is for the revenge of my son's death. That is what made me do it.
"Before this I had stated to a doctor that I felt like killing people, but up until my son's death I had not killed anyone.
"My son's death was the biggest thing that ever happened to me, because I loved him so much - and he meant the world to me and after his death I just seemed to go to the pack.
"I feel no wrong for what I have done because at the time that I did it I didn't think it was wrong. But after my son was killed I tried to kill my wife and I was admitted into Parramatta Psychiatric Home because I knew I needed treatment. So I signed myself in and I was there for a number of weeks.
"I think, if given the chance, I will kill again, for the simple reason that I have to kill seven people, and I have only killed three, which means I have four to go, and this is how I feel in my mind, and I just can't say that I am not going to kill anyone else, because in my mind I am.
"Whether you think I am sane or insane is up to youse [sic] but I would say that I was definitely insane at the night of these murders. The day of my son's inquest at the Coroner's Court happened to be the day that I stabbed Mr Anson. The reason why I killed this man was because I heard my son's voice tell me to do so. The same with the second and third person.
"Each time I went to the graveyard to visit my son's grave a violent streak would come over me and I wanted to be so violent I wanted to kill people. I kept hearing voices, not only my son's voice, but other voices as well, which I don't know whose they are.
"On the Thursday that I was apprehended I had every intention of killing Rick Webster as I heard the voices to tell me to do so and anyone else that the voices tell me to kill I would kill until I reached the figure seven.
"I still say I felt no wrong in what I have done and I am still willing to kill anyone else that I am told to kill. At the time of my son's death I took it pretty hard and since then I have not been the same because I loved him so much and I believe in my own mind that my wife murdered him on purpose and that is why I killed these men, for the revenge of my son's death.
"And this is the honest truth. So I hope that the jury and Your Honour will believe what I said. That's it."