The Independent Police Complaints Commission has criticised two officers who responded to a disturbance at a house, two hours before a woman was murdered by her partner.
Ian Hope, 53, stabbed his partner, Sarah Gosling, 41, to death in Lemington, Newcastle, in February.
Errors on the police computer meant a history of domestic abuse in their relationship wasn't attached to his address.
But the IPCC found two officers who attended the house on the night of the murder did not investigate thoroughly. They did not ask for Mr Hope's name and did not run a computer check on him.
If they had, his abusive past would have been linked to him.
"The lack of information undoubtedly dictated a certain mindset for the officers on that occasion and as a result they only identified the incident as being one of anti-social behaviour. This possibly resulted in their lack of diligence in making their enquiries. Tragically that specific incident was a precursor to Ms Gosling's murder.
"Although we can say there was a missed opportunity, we cannot speculate that if the officers had the information about the couple's history they would have identified an ongoing abuse situation and prevented the murder.”
More top news
The Environment Agency says there is a reduced risk of flooding around the River Tees after they moved fallen trees and debris.
Thousands of pieces Sci-Fi related Vehicles and Robots, which have been collected since the 1930s, are going to be auctioned in Stockton
A meeting in Darlington will highlight the opportunities that two of the UK's rail projects could have for Tees Valley companies.