Mr Hall said: “It may be that exchange set the seed in Zak’s mind that they would be better off without Zakari.”

Two doctors, relied on by the defence, say they believe that Bennett-Eko reaches the legal threshold for being declared insane.

Dr Higgins and Dr John Crosby, both psychiatrists at the secure hospital Bennett-Eko is currently residing in, say the patient truly believed his son to be the devil and thought “killing the devil is not wrong”.

Dr Crosby said that Bennett-Eko’s lack of attempt to save his son shows “how grossly disturbed his mental health is”, after evidence that the defendant had been a caring father previously.

A memorial was also set up to honour little Zakari (Image: MEN Media)
“He seemed very confused and may have been hearing voices as his eyes were looking around unusually. He did not look like he was aware of his surroundings,” said the doctor.

“Although he did know what he was doing was wrong, he did not know what he was doing was wrong.

“He believed due to hallucinations that his son was the devil, and therefore it’s not legally wrong to kill the devil.”

During his evidence, psychiatrist Dr Inti Qurashi said the defendant told him he hesitated before he threw Zakari into the river and thought: “What the f*** am I doing.”

And summing up the case, judge Mr Justice Fraser said: “Dr Qurashi said he considered the hesitation before the baby was thrown into the river an important point and said it showed the defendant knew what he was about to do was wrong.”