A young mother was beaten to death by her violent ex-partner in front of her two-year-old daughter after police failed to intervene 11 times, investigators have said.
Casey Brittle, 21, repeatedly called Nottinghamshire Police before she was murdered by Sanchez Williams.
Amerdeep Somal, a commissioner at the Independent Police Complaints Commission, said Williams, from Nottingham, was "well-known to local police for his propensity for violence and threatening behaviour".
"In this case it is clear that a number of officers failed to perform to the level expected of them and basic actions, that may have helped others see the full picture of her suffering, were not completed," the commissioner said. "No consideration was given to why Casey was reporting domestic abuse but then subsequently saying that she did not want police help."
Ms Brittle died from a series of injuries to her head, including a fractured jaw, cuts and bruising in October last year.
Williams, of Lathkill Close, was jailed for life after he admitted murdering Casey at her home. His minimum term of 15 years was increased to 20 years by the Court of Appeal in June after the Lord Chief Justice, Lord Judge, agreed the original sentence was "unduly lenient".
One of the aggravating features of the case, said Lord Judge, was that the small child had "witnessed the murderous attack on her mother by her father". The judge said: "We simply cannot guess the long-term damage which will have been caused to that little girl and we can only hope that her future happiness is not irretrievably damaged."
In a statement, Paul Broadbent, assistant chief constable of Nottinghamshire Police, said the force unreservedly accepted the recommendations of the report and that he deeply regretted Ms Brittle's death and the circumstances surrounding it and had apologised to her family.
Six officers have appeared before a misconduct meeting and admitted their individual failings in relation to the case. One received a written warning while three received management advice, Mr Broadbent said. No action was taken against the remaining two.
Four others, who were not required to attend the meeting, have been subject to unsatisfactory performance procedures, he added.