A police officer demoted over the investigation into the death of Poppi Worthington is to retire.
Poppi was 13 months old when she was found with serious injuries at her home in Barrow, Cumbria, in December 2012.
Det Insp Amanda Sadler, of Cumbria Constabulary, admitted gross incompetence and was demoted to the rank of sergeant.
The force has now confirmed that she has announced she will retire next month.
Following the youngster's death, a family judge ruled that on the balance of probabilities, Poppi had been sexually assaulted by her father, Paul Worthington.
Mr Worthington was questioned on suspicion of sexual assault but never charged with any offence. He denies any wrongdoing.
A police spokesman said: "Cumbria Constabulary can confirm that an officer, who was demoted following performance proceedings concerning the initial investigation into the death of Poppi Worthington in December 2012, has announced their decision to retire.
"Their retirement date is set for mid-November 2016."
The demotion was announced by the force earlier this month.
Performance proceedings were held in front of a panel, which was chaired by an independent senior officer from outside the force.
Det Insp Sadler admitted her actions in relation to the initial investigation into Poppi's death amounted to gross incompetence and the reduction in rank was enforced immediately.