UK police are failing to tackle human traffickers and slaver drivers, who are left to offend unchecked, a report has said.
A study by HM Inspectorate of Constabulary and Fire and Rescue Services revealed that cases of slave driving and human trafficking are suffering delays, being prematurely shelved or being overlooked entirely.
These shortcomings are failing victims, who are often left to suffer at the hands of the perpetrators, the report warned. In some cases, the victims were arrested as offenders.
Figures published by Sky News after an FOI request underscores the scale of the problem. The conviction rate for modern slavery offences in England and Wales stands at just 1.9%, with only 25 successful prosecutions from 1,265 offences reported by police forces between April 2015 and March 2017.
Some 38 police forces recorded a 200% rise in the number of crimes reported under the Modern Slavery Act, while an August report by the National Crime Agency revealed modern slavery and human trafficking affects "every large town and city" in the UK.
According to the HM Inspectorate, senior police showed "variable commitment" to tackling human trafficking, or to proactively look for offences.
"Whilst modern slavery cases can be complex and require significant manpower, many of the shortcomings in investigating these cases reflect deficiencies in basic policing practice," said HM Inspector of Constabulary Wendy Williams, who led the probe.
"We found inconsistent, even ineffective, identification of victims and investigations closed prematurely. As a result, victims were being left unprotected, leaving perpetrators free to continue to exploit people as commodities."
Offences that fall under the umbrella of modern slavery include forced labour, sexual exploitation and domestic servitude, with nail bars, brothels and car washes often targeted by police.
The report said victims are let down "at every stage" by failings that include premature case closures, delays of up to eight months in starting investigations, and substandard safeguarding of potential victims.
The study highlighted several victims who were failed by police shortcomings, including a woman forced to work as a prostitute. Despite reporting her experience to police, no rape charges were brought.
Immigration services contacted police about another victim, who was being flown into the country on a private jet for domestic servitude. Police failed to open an investigation.
Some officers did not think modern slavery was an issue in their area, the report added, though it did acknowledge some forces had begun to improve their service.
"We fully accept the recommendations included in this report,” said Shaun Sawyer, the national policing lead for modern slavery.
"The police service is now actively seeking out and uncovering modern slavery. Across England and Wales there are currently over 400 active investigations, an increase of 218% from November 2016 - 85% of which are led by the police.
"The policing challenge ahead is considerable but we are committed to building on our achievements and improving our approach so we consistently safeguard victims and crack down on those who make profit from people."
A Home Office spokesman said the Government is investing £8.5 million to help the police tackle the "barbaric" crime of modern slavery.