Domestic abuse case increase could 'overwhelm' police
Her Majesty's Inspectorate of Constabulary said cases of reported abuse soared by 31% between 2013 and 2015.
The quality and speed of abuse investigations are suffering under the strain, the police body said in its report.
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Zoe Billingham, the HM Inspector of Constabulary, warned that police were struggling from the “excessive” workload.
The report shows improvement on 2014's assessment, which condemned the “significant weakness” the service offered to victims of domestic abuse.
This year's report suggests the recording of cases has improved, as had the encouragement of victims to come forward.
But it also offered a string of criticisms, including a lack of evidence police were engaging with victims for feedback and the mixed attitudes of officers risking victims' trust.
An “over-reliance” on e-learning training and a “wide variation” of arrest rates in domestic abuse cases were also highlighted.
In a separate report, HMIC found 31 out of 43 forces needed to protect vulnerable people better.
Ms Billingham said: "We witnessed a clear commitment from forces to improve the service they provide to vulnerable people generally. This determination now needs to translate into effective and consistent support and protection."