Poppi Worthington
Poppi Worthington was just 13 months old when she was found dead in her home Family photo

A father who was ruled to have sexually assaulted his 13-month-old daughter in the hours before she died has fled the country as the Crown Prosecution Service (CPS) revealed they will review the case. Paul Worthington was arrested after his daughter Poppi was found with serious injuries in December 2012 - but was never charged with any crime.

Mr Justice Peter Jackson ruled on 19 January at Liverpool High Court that the 48-year-old, on the balance of probabilities, "perpetrated a penetrative assault" on his daughter on the night she died after he watched porn, he said involved adults, in his room. Worthington was arrested afterwards on suspicion of sexual assault but was not charged with any offence after a botched investigation by Cumbria Police.

He has always denied that any assault took place but now the CPS has said that, following the damning family court judge findings, they will be reviewing the file. Worthington completely rejected the judge's findings on 20 January.

The court had heard how, according to her father, Poppi awoke screaming at around 5.45am. She was rushed to hospital but died. She was found to have had a fracture of her right lower leg and other acute injuries which were said to be very rare in a girl her age.

Worthington has now left the country according to his sister, Tracy, who said that her brother had suffered death threats before he left. She added that he was trying to get legal advice as he tried to prove his innocence.

She told the Guardian: "He has had to leave the country because of all of this. People keep knocking on my door asking where he is, thinking he is going to be wandering around my estate, but he is not here. He left the country on Tuesday. He is hundreds of miles away."

In a statement, the CPS said: "We received a file from Cumbria Police in relation to the tragic death of a 13-month-old girl in December 2012. We conducted a thorough review of the evidence in accordance with the Code for Crown Prosecutors.

"This review included consideration of expert evidence which was carefully considered by the prosecutor, who took advice from experienced counsel. We decided there was insufficient evidence to provide a realistic prospect of conviction and therefore no-one was charged with any offences relating to her death. Following the findings of the family court judge, we are now reviewing the case."

Justice Jackson also criticised Cumbria Police for the way it handled the investigation into the toddler's death as the force was found to have failed to preserve vital items for forensic analysis, did not properly secure the scene, check Worthington's phone calls, botched forensic analysis of clothing, and lost evidence. All the medical experts who reviewed the case agreed the cause of death is "unascertained".

Cumbria Police referred themselves to the Independent Police Complaints Commission (IPCC) for the way they dealt with the investigation. The IPCC said that a serving Cumbria Police officer would face a "performance meeting" while another officer received "management action".

It said in a statement: "As a result of the evidence we presented, one serving officer is to face a third stage performance meeting - which has the power of dismissal if gross incompetence is proved. A second officer has received management action. A third officer cited in the report has since retired from the force."