The force has been graded as ‘requires improvement’ in all areas inspected by Her Majesty’s Inspectorate of Constabulary and Fire & Rescue Services (HMICFRS) in 2017.
The report, published today (Thursday), says excessive workloads for officers and staff mean the force is unable to meet the demand it faces.
But it acknowledged that the building blocks for more effective policing are in place.
The inspection found some crimes are being recorded incorrectly and several incidents had been wrongly assigned to the telephone investigation team because not enough response officers were available to attend immediately.
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In some less serious investigations, the force was found not to be completing initial inquiries satisfactorily.
It also found the force to have a ‘serious’ shortage of investigators, although it recognised it is increasing its number of trained investigators.
The report said: “The quality of the force’s investigations remains inconsistent.
“It does not always allocate them to appropriately trained staff or supervise them fully.
“As a result, victims of crime sometimes receive a poor service.”
Northamptonshire has one of the lowest rates of cases where a charge of summons is brought (8.5 per cent).
The report said: “This means that some perpetrators may not be being brought to justice, and fewer victims may have the outcomes they should have been able to expect.”
The force also needs to improve its management of registered sex offenders, ensuring it completes visits with appropriate timescales to protect the public.
The report added that Northamptonshire Police’s new policing model is expected to sort out many of the problems highlighted by HMICFRS.
It said: “The force’s change programme, known as the service delivery model (SDM), aims to resolve many of these problems.
“This new model is expected to align resources to meet demand better, allowing officers and staff to concentrate more on dealing with the priorities of the force and its communities.”
Chief Constable Simon Edens welcomed the report’s findings, adding that the force was responding dynamically to tackle many of the areas identified as requiring improvement.
He said: “I welcome this report and am reassured that many of the areas for improvement were already being identified and addressed at the time of the visit.
“Since then, a tremendous amount of work has gone into improving our processes, including how we tackle serious and organised crime and raise the quality of our investigations.
“Our new service delivery model, launched around the time that HMICFRS visited in October 2017, is now embedded and has radically restructured the way the force operates, for example in making our neighbourhood officers more accessible, our response teams better placed to react and our overall community engagement work bordering on excellent.
“Northamptonshire Police’s core purpose is to protect people from harm and I am satisfied that the entire workforce, led by our frontline officers, are responding robustly to the areas of concern identified and that we now have a whole force approach to making significant, positive progress to that end.”
The county force added that major steps had been taken to improve the way it tackles serious and organised crime, which includes gang-related issues, CSE and Asian gold thefts.
Stephen Mold, police and crime commissioner for Northamptonshire, said he is unhappy with the rating and has made Chief Constable Edens aware of his feelings.
He said: “I have worked with the chief constable to provide the resources he has identified as being required to make Northamptonshire safer.
“I believe the foundations are in place but I am frustrated at the speed at which change is being implemented.
“I have made clear to the chief constable that we need to see the ongoing work delivered at a faster pace.
“The staff and officers of Northamptonshire Police are doing a fantastic job under challenging conditions, and I know that they go above and beyond the call of duty day in, day out to keep Northamptonshire safe.
“I continue to say thank you for their hard work on our behalf.”
Mr Mold added that he is ‘content’ with the plans laid out to improve the force.
He said: “I’m pleased that HMICFRS have acknowledged some change in the right direction, however I reiterate that this needs to be pro-actively continued by the chief constable and chief officer team to ensure that the people of Northamptonshire receive a service to the standard they deserve.
“The chief constable has shared with me how he plans to improve the issues identified and I am content with these plans at present.
“I will continue to both work with the chief constable and hold him to account accordingly.
“Within my remit I remain focused on building public confidence, knowing that we have plans in place to improve efficiency through better use of technology and more effective use of our buildings and estates, which will deliver significant change.”
Nationally one force was found to be ‘outstanding’, 30 forces were ‘good’, 12 ‘required improvement’ and none were ‘inadequate’.