Woman sentenced for killing two-year old daughter found in a pond

A woman suffering from a severe mental health condition has today been sentenced to four years' imprisonment for killing her two-year old daughter in September 2023.

Alice Mackey, 42, of Kingsley, Hampshire, drowned her daughter, Annabel Mackey.

On Sunday 10 September 2023, Mackey called the police to report that Annabel had gone missing, that she had put her to bed and returned an hour later to find she was not there. Whilst on the phone to the emergency services, Mackey lied to the operator and told them she had gone outside and couldn’t see her daughter, walked towards the pond and found her in the water. Mackey told the operator that someone must have entered the house and taken Annabel.

A thorough investigation from Hampshire Constabulary showed that Mackey’s account was untrue and that she was responsible for drowning her daughter.

When it became apparent that Mackey had drowned Annabel, she was charged with murder. A decision was later taken that she should be prosecuted for the offence of manslaughter by way of diminished responsibility. This decision was taken after Mackey had been assessed by three psychiatrists, including a very eminent psychiatrist instructed by the Crown Prosecution Service. The three psychiatrists agreed that Mackey had been suffering from a severe mental health condition at the time she had taken Annabel’s life.

In July 2025, Mackey pleaded guilty to the manslaughter on the grounds of diminished responsibility in relation to her daughter’s death.

Anthony Johns, of the Crown Prosecution Service, said: “Everyone who has been involved in this case has been deeply moved by the tragic circumstances of Annabel’s death. I would like to pass on my personal condolences to the family of Annabel. I have been personally touched by their strength and dignity in this deeply distressing time.”

Building the case

Diminished responsibility is only a partial defence to murder because it results in a conviction for manslaughter. It is for the defendant to prove that it applies.

When deciding whether to proceed with a charge of manslaughter instead of murder, the CPS must be satisfied that there is sufficient evidence that the defendant’s actions were sufficiently influenced by her mental illness, that her ability to exercise self-control were impaired, and that a jury would come to the same conclusion.

In this case, the evidence that Mackey’s actions were significantly impaired by postpartum psychosis and her deteriorating mental illness that flowed from that. The evidence from three expert psychiatrists was subjected to a very thorough and detailed review.

We reached the conclusion that, considering the compelling psychiatric evidence, there was no longer a realistic prospect of conviction for murder and that she should be prosecuted for manslaughter by reason of diminished responsibility.