Ms Johnson's decision to withdraw her claim emphasises the weaknesses of the case and highlights the determination of the force to protect its reputation

Assistant chief constable Graham Barker

Ms Johnson, of Warrington, Cheshire, continued in the job for four years after James was murdered by two 10-year-old boys.

She but left on ill-health grounds after failing to win promotion to head of department.

Last year, she lodged a claim for damages alleging that the force had failed her in welfare terms.

The case was due before the county court in Liverpool next month but it was revealed on Thursday that Ms Johnson had withdrawn her claim.

Assistant chief constable Graham Barker said: "Ms Johnson's decision to discontinue her claim for compensation highlights the need for the force to robustly and vigorously contest any claim which challenges the integrity of the Force and our established procedures for caring for the welfare of our staff.

Denise Fergus received �7,500 compensation

"Merseyside police contested Ms Johnson's claim throughout, in the belief that wrongful claims have serious potential to damage theforce's reputation and the professionalism and dedication of its staff.

"Ms Johnson's decision to withdraw her claim emphasises the weaknesses of the case and highlights the determination of the force to protect its reputation.

"Clearly there will be wholly legitimate claims from staff who believe they have suffered trauma in the course of their duties and we will continue to support them wherever possible.

Mental problems

"However, we need to scrutinise each claim to ensure only worthy and legitimate claims receive attention."

Ms Johnson claimed several other high-profile murders took their toll including one involving Liverpool couple Gary Pettitt, 25, and Jean Larkin, 24, shot dead and burnt on a bonfire near Chorley, Lancashire in 1993.

She also claimed to have suffered mentally from dealing with the 1995 murder of Paul Barker, 13, and Robert Gee, 12, at a fishing pond in Eastham, Wirral.