Michael Te Kouarehu Kereopa has been charged with the murder of six-month-old Gracie May McSorley in the Porirua District Court Today.
The initial charge Kereopa faced in July this year of assaulting a child was upgraded to murder today after police received expert medical advice.
Gracie died as a result of severe head injuries that police say were inconsistent with Kereopa's claims of an accidental fall.
Police allege that "Gracie's injuries, similar to those that would be sustained in a high-speed car crash, are non-accidental and were deliberately caused by the defendant."
31-year-old Kereopa had been in a brief relationship with Gracie's mother at the time of her death.
According to a Police statement on Monday 6 July this year, Gracie's mum left to collect an older sibling and when she left, Gracie was alert, happy and healthy.
When her mother returned 45 minutes later it was clear Gracie was very unwell.
The defendant was the only person in the home with Gracie during this time.
An ambulance was called when Gracie became unresponsive and she was air-lifted to Wellington Hospital and placed on life support, however she passed away on Tuesday July 7.
Police say they are pleased that thorough investigative work has identified the defendant as the alleged offender in this case, however emphasised this tragedy as yet another sad reminder of New Zealand's unacceptable levels of child abuse.
They say, "Now a family is mourning the loss of a beautiful little girl at the hands of someone she should have been able to trust to care for her."