The number of people barred from working with children as a result of committing sexual offences against youngsters has plunged since vetting and barring legislation was changed three years ago, Labour has claimed.
Figures obtained by the Opposition using Freedom of Information (FoI) laws show 12,360 people were stopped from working with children in 2011 due to committing sexual offences against youngsters. This fell to 5,758 in 2012 and 2,800 in 2013.
Other data shows the number of people being barred from working with children as a result of intelligence sharing and investigations by the police and Disclosure and Barring Service (DBS) has fallen from 1,542 in 2011 to 471 in 2012 and to 351 in 2013.
Labour has claimed changes made by Home Secretary Theresa May have played a significant role in these reductions as her reforms made it harder to bar a convicted sex offender.
Yvette Cooper, Shadow Home Secretary, said: "Theresa May was warned repeatedly that the new legislation left major loopholes in the system.
"This evidence shows those warnings were right."
She went on: "Parents want to know that if someone has committed serious abuse against children or has a history of grooming or sexual abuse, they will not be allowed to work with children.
"And schools, sports organisations and other groups need to be able to have confidence in the vetting and barring system.
"Child protection is immensely important and it must not be put at risk because of faulty legislation or failures in the Home Office system."
Barring based on conviction was changed by legislation.
For all but a handful of offences, only those actually working with children or expressing a desire to work with children are added to the barred list, while those in other occupations are not added.
A Home Office spokesman said: "It remains the case that anyone committing the most serious offences is still automatically barred from working closely and unsupervised with children.
"The coalition Government introduced changes to the barring regime to apply common sense levels, but if someone applies to work with children any serious criminal records or police information are still considered when checks are carried out and, if necessary, they will be barred.
"The changes strike an appropriate balance between avoiding unnecessary intrusion into people's lives and ensuring that children and vulnerable groups are protected."
An NSPCC spokesman said: "These figures add to our concerns that the pendulum may be swinging in the favour of abusers' rights rather than child protection.
"The dramatic drop in the number of people being barred is concerning and the Disclosure and Barring Service needs to explain why this has happened in a transparent way to reassure that the current system is fit for purpose in terms of its contribution to protect children.
"Given the number of sexual offences against children has not fallen in line with the number of people being barred, it would seem timely for a review of the implementation of the service to take place to ensure that children are being adequately protected."