A father who murdered his baby daughter by snapping her spine in two was yesterday jailed for a minimum of 22 years.
James Howson twisted the arms and legs of the 16-month-old girl before breaking her back over his knee.
In the two months before the final barbaric act, jobless Howson, 25, had inflicted more than 40 injuries to his daughter, Amy.
He had had a violent streak ever since his teenage years and at the age of 14 was expelled from school, Leeds Crown Court heard.
A teacher noted at the time: 'This boy will commit a murder before too long. I've never seen such a disturbed young man.'
He had a history of violence to women and was addicted to cannabis, smoking the drug each day.
Jailing him for life, Mrs Justice Cox said he had shown no remorse for the 'chilling and brutal' murder.
'The bone was completely dislocated, resulting in spinal shock, rapid unconsciousness - mercifully - and to death,' she said.
'The force you used upon her must have been considerable.'
Howson had 'cruelly and deliberately' assaulted Amy in the weeks before, she added, breaking her ribs and limbs. She was dehydrated and covered in bruises and was screaming with pain.
Finally, days before Christmas last year, he laid her face up across his knees and pressed down with such force that he snapped her spine.
At the time the malnourished toddler, an only child, weighed only 13lb 7oz. Howson sat with her body at the home in Doncaster, South Yorkshire, until the next morning, December 23, when police were alerted.
After his arrest he claimed that the child had fallen out of bed and banged her head.
He then tried to blame his Staffordshire bull terrier and finally his partner, Tina Hunt, 26.
But earlier this week a jury found him guilty of murder and cruelty on the 'clearest of evidence'.
Hunt, who is of low intelligence, was given a 12-month jail sentence suspended for two years after she admitted allowing the death of a child and one charge of cruelty.
Amy, who was born in August 2006, was last seen by health workers in March 2007.
The court heard they could not get in the house for further checks after Howson fitted security cameras to vet visitors.
Although present at the time of the murder, Hunt - who was pregnant with the couple's second child - did nothing to warn the authorities about what was going on because she lived in fear of Howson, who did not want another child.
Outside court, Amy's grandfather Colin Hunt, 48, said: 'Howson should have got longer. He killed a 16-month-old baby and should not be let out of jail at all.'
Detective Superintendent Carl Sturgess, who led the investigation into the murder, said: 'The catalogue of injuries were some of the worst I have seen in 30 years of policing.
'Matters began to deteriorate within this household from October 2007 and steps were taken to ensure this child was not seen by anyone from the medical authorities.'