Two officers from Northamptonshire Police have been criticsed by a watchdog after murdered David Miller's body was found days after calls from concerned members of the public.
Mr Miller's dismembered body was found in his flat in Patterdale Walk, Boothville, on June 14 2016, and four homeless people were later found guilty of killing him.
But it has now emerged from an investigation by the Independent Office of Police Conduct (IOPC) that "several" calls were made to police by neighbours with suspicions that Mr Miller had been killed, as early as three days prior.
The summary report, which does not name the two control room-based police officers, says: " There were lines of enquiries that could have been pursued by the police before the incident logs relating to some of these calls were closed."
Investigators say there was an indication at the start of the investigation the two officers "may have behaved in a manner which would justify the bringing of disciplinary proceedings".
But the inspector and sergeant were interviewed about their decision to close incident reports that arose out of the concerned phone calls, and several witnesses were also spoken to by the IOPC. Investigators concluded that a tribunal would find they had no case to answer.
However, the investigator believed that "the performance of both may be considered to be unsatisfactory."
The outcome was that Northamptonshire Police "agreed to address the issues of individual performance and referred the matter to the two officers’ line managers."
The IOPC said Northamptonshire Police could improve by recording the reasons why they shut down enquiries.
Street drinkers Joseph Catlin, Michael Hallett and Zena Kane were jailed for life for Mr miller's murder and Ian Cuthbertson was handed a sentence of seven-and-a-half years for manslaughter.
A police spokeswoman said: “Firstly, we would like to offer our sincere condolences to the family of David Miller for the loss of their loved one in such tragic circumstances.
“Northamptonshire Police referred itself to the IPOC following Mr Miller’s death in June 2016 for them to examine how initial reports relating to his murder were handled. They found that there were some issues regarding our initial response, which, although not meeting the threshold for disciplinary action, fell below the high standards the force expects of its officers.
“The two officers’ performances have been addressed appropriately by their line managers to ensure that the issues which arose do not occur again and learning from this incident has also already been implemented and is monitored regularly.
"The circumstances surrounding Mr Miller’s death were fully investigated and resulted in the conviction of four people for murder or manslaughter who received custodial sentences totalling more than 68 years."