Eight years after the Soham murders, a new report has revealed that some schools in Cambridgeshire are failing to check teachers' criminal records before hiring them.
Despite a raft of safety procedures being introduced since Soham Village College caretaker Ian Huntley murdered 10-year-olds Holly Wells and Jessica Chapman in 2002, there are "regular" instances of schools failing to carry out Criminal Records Bureau (CRB) checks before employing staff in the county.
A report from Cambridgeshire County Council's audit and accounts committee said pupils were being put at "significant risk" by schools flouting security guidelines, warning there were "significant weaknesses" in ensuring the necessary checks are completed.
Headteachers expressed concern about the report, with one principal warning that taking risks when employing new staff was "potentially fatal".
As a result of the Bichard Inquiry, which examined the failings that allowed Huntley to get a position at Soham Village College despite previous allegations of rape, indecent assault and sex with underage girls against him, all school staff should be subjected to enhanced CRB checks.
But the report to the council's cabinet, drawn up after visits to 16 schools between December 2009 and April 2010, said: "Most concerning are the regular instances of schools allowing employees to begin work without completing the required set of pre-employment checks. If findings are representative of the wider picture, this area continues to remain a significant risk."
Overall, the county was given a "moderate" rating for safe school recruitment for the third year in a row - despite "a number of reminder letters issued in previous years".
"The members noted the large majority of schools have acceptable practices and some improvement against previously reported audits was found," the report said. "However, appointments were still being made in some schools before all relevant ... checks had been received."
Adrian Loades, the council's executive director of children's and young people's services, has written to all heads reminding them "in the strongest terms" of their responsibilities for vetting staff.
"Whilst some schools may consider that risks can be managed locally, there should be no circumstances where employees begin work without completing the necessary background checks," he said.
Russell Hobby, general secretary of heads' union the NAHT, said: "Schools should be completing CRB checks and need to be extremely cautious."
But he added that there can sometimes be "long delays" in getting them completed, causing frustration for schools.
Ben Slade, principal of The Manor School in Cambridge, said: "Although all the CRB does is prove that, at that moment in time, that person hasn't been caught doing anything wrong, to take the chance of not doing it is at best ill-advised and at worst, as we have seen in our own county, potentially fatal."
In June, Somerset County Council revealed five out of 10 schools it had inspected failed to adhere to the correct procedures, with six people getting jobs before they had been CRB cleared.