Detained foreign suspects' police records go unchecked
Some police forces in England and Wales are failing to check the criminal records of the vast majority of foreign nationals they arrest.
When checks are carried out, as many as one in three foreign suspects turns out to have previous convictions abroad.
But 5 live Investigates found while many forces often consulted foreign records, the rate in Cleveland was only about 6% and in Greater Manchester 8%.
The police say improvements are needed but the UK compares well within the EU.
A Home Office spokeswoman said the department would "use every possible power to stop foreign criminals from coming into this country".
The spokeswoman insisted that all passengers were checked against police, security and immigration watch lists on arrival and individuals who posed a risk were refused entry.
In October, the government spending watchdog, the National Audit Office (NAO), issued a report called Managing and Removing Foreign National Offenders.
It revealed that last year police had cross-checked the criminal records of only about 30% of people from overseas they arrested.
'Serious criminal history'
One of the report's recommendations was that officers should refer more foreign arrests to the Association of Chief Police Officers' Criminal Records Office (Acro), which has access to overseas police files.
"Of those checks that were done last year [on detained foreigners from within the EEA], one in three came back with the result that the arrested foreign national had a serious criminal history," said Toby Evans of the NAO.
"If those checks are not done, the key point when foreign nationals can be detained in police stations and removed from the country is being missed."
New figures obtained by 5 live Investigates show that forces are now requesting more checks.
Some, such as the Metropolitan Police and Hampshire, are now running background checks on all offenders arrested.
That is also the case with Derbyshire Police.
In one instance there, a man accused of assaulting his wife turned out to have been convicted of aggravated murder in his home country of Lithuania.
He is now facing deportation.
In Greater Manchester 6,836 foreign nationals were arrested last year, but in October just 8% of foreign nationals detained that month were checked.
In Cleveland, 966 foreign suspects were detained in the year, and in October checks were run on just 6% of those detained that month.
Ch Insp Steve Young of Cleveland Police said: "The force accepts that vast improvements need to be made and work has already begun to address this issue.
"Our ultimate target is to achieve 100% compliance and it is an absolute priority for me to increase our rate of referrals [to Acro]."
A nationwide target has been set to check at least 60% of arrested foreigners from within the EU.
"This is never going to be one of those situations where you flick a switch and everything happens immediately," says Acro chief executive Ian Readhead.
He says better training and an upgrade of IT systems are needed if the target is to be reached.
"Significant improvement is needed in some areas but when compared across the European Union, we're very much at the head of this game," said Mr Readhead.
The checks proved vital in many cases, he added.
"Very often we arrest people for minor offences, only to discover that their history is one of committing serious offences in Europe.
"I have no doubt that every chief constable is completely committed to ensure that every foreign national is checked."
This report will be broadcast on Sunday, 14 December 2014 at 11:00 on BBC Radio 5 live.
You can listen to other editions of 5 live Investigates on the BBC iPlayer.