A mother who drowned her disabled daughter in a bath because she was embarrassed by her cerebral palsy was jailed for life yesterday.

Joanne Hill, 32, tried to persuade her husband, Simon, to have four-year-old Naomi adopted and, when he refused, hatched a plan to murder her.

Hill, an advertising executive, was ashamed of Naomi’s condition, which meant that the little girl had to use callipers to help her to walk, Chester Crown Court was told.

Hill denied murder on the grounds of diminished responsibility, claiming that she was suffering from a severe mental illness at the time of the killing. But a jury took only 1 hour 20 minutes to find her guilty of murder after a two-week trial.

Mr Hill described his wife later as “evil” and said that Naomi was his “little princess”.

The jury heard that Hill, of Connah’s Quay, North Wales, had been drinking regularly and had cheated on her husband with a colleague days before the killing.

She told police she decided earlier that day to kill Naomi and herself.

After leaving her office she went to a pub where she had a glass of wine before collecting her daughter from a childminder.

During the drive home she stopped at a supermarket to buy more wine where she laughed and joked with the shop assistant. At about 6pm, they arrived home and Hill immediately ran a bath while Naomi watched television. As the bath filled, Hill added bubble bath and drank another glass of wine before picking up her daughter and carrying her upstairs.

She stood Naomi up in the tub, then forced her to sit down and thrust her head under the water, holding her there for between 5 and 19 minutes.

A harrowing tape recording of Hill describing how she drowned Naomi had been played to the court. “I pushed her down,” Hill said. “I held her down by the head. She’s lying on her front with her face to the side. I am holding her by the neck, around her neck. I am holding her against the bottom of the bath. She did not come up.

“I told her to sit down. I was being forceful with her. I said, ‘come on, you are having a bath’, and told her to sit down. I held her by her head and neck area, on the back area of her neck and head - it just happened so quick.”

Hill said in a separate statement: “She was a bit whingey but not a lot. I got hold of her neck and pushed her in the water. She turned on to her right side after a while - I think she’d gone, she’d stopped moving.”

After killing Naomi on November 26 last year, Hill dressed her body in dungarees, a duffel coat and pink trainers, and placed her in the child seat in the family car.

She bought a bottle of wine and drove around Chester, drinking for eight hours. CCTV images showed Hill joking with staff at a petrol station while the child lay dead in the car. Eventually, she took Naomi’s body to a local hospital.

The court was told that Hill’s mental illness first became apparent when she was 17 and saw a child psychiatrist for anxiety and repetitive thoughts. She twice attempted suicide in 2000 and shortly after Naomi’s birth she suffered puerperal depression – a severe form of postnatal depression.

Judge Elgan Edwards, QC, Recorder of Chester, sentenced Hill to a minimum of 15 years in jail. He said: “You could not cope with the child’s disability such as it was. You had other pressures upon you such as a disintegrating marriage and you decided to kill your own daughter by drowning.

“There can be no excuse for what you did. I’m afraid you must now pay the penalty.”

After the sentencing Mr Hill, 38, a senior fleet controller at a car rental company, said: “It has been said in court that Naomi suffered from cerebral palsy. This is not true; she did not suffer at all. She lived life to the full and was an inspiration to us all.

“Naomi took everything in her stride and enjoyed everything. She was my constant companion; she was my best friend. She was my little princess.”

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