Q&A: 'Sarah's Law' explained
Sussex Police is the latest force in England to introduce the Child Sex Offender Disclosure Scheme, often referred to as "Sarah's Law".
BBC News explains what the scheme, due to be rolled out to all forces across England and Wales by spring next year, is all about.
What is the scheme?
The Child Sex Offender Disclosure Scheme, or "Sarah's Law", allows parents to ask police if someone with access to their son or daughter has been convicted or suspected of child abuse.
Officers will look into the background of individuals and reveal details confidentially if they think it is in the child's interests.
Previously, a parent could alert police to concerns about someone, but there were no clear rules about whether or not they should be told anything if child protection officers discovered cause for concern.
Police can also warn parents if concerns are raised by grandparents or neighbours.
Sara Payne, the mother of eight-year-old Sarah Payne who was murdered by a convicted sex offender in West Sussex in 2000, has been campaigning for the government to bring in such measures since her daughter died.
What happened in the pilot?
The pilot started in 2008 and involved four police forces in Warwickshire, Cambridgeshire, Cleveland and Hampshire.
It was a year-long project, which was hailed as a success by the Home Office. Ministers said it had protected 60 children.
Nearly 600 inquiries made to the four forces involved led to 315 applications for information and 21 disclosures about registered child sex offenders.
A further 43 cases led to other actions, including referrals to children's social care and 11 general disclosures were made regarding protection issues linked to violent offending.
Which forces use the scheme?
The four pilot forces, plus Sussex, West Mercia, Bedfordshire, Norfolk, North Yorkshire, Thames Valley, West Midlands, Essex and Suffolk, have already introduced the scheme.
It is being rolled out this autumn in Northamptonshire, Staffordshire, Leicestershire, Wiltshire, Cheshire, Durham, Northumbria, Dorset, Lincolnshire, Surrey and Gloucestershire.
The remaining areas will introduce the scheme by spring next year.
Are there any concerns?
There were fears the scheme could drive child sex offenders underground, or cause vigilante-style attacks.
In the US, Megan's Law, which allows much more disclosure, including the publication of names, addresses and pictures of paedophiles in some states, has experienced such problems.
Under the UK scheme, a parent who is given information is not allowed to pass it on to other people.
The pilot did not throw up any such problems, but children's charities have warned that monitoring of the scheme must continue as it is rolled out nationally to ensure this does not happen.
What do the charities say?
Children's charities have welcomed the national roll-out, but have also warned the government to be cautious.
Jon Brown, head of strategy and development at the NSPCC, said it was important that the scheme did not "lull people into a false sense of security" about sex offenders.
"The majority of sexual abuse happens in the home or in the extended family and the majority goes unreported," he said.
"The notion that a member of the public contacts police about someone they want to check and they check them and say they have no concerns about them could create a false sense of security."
Enver Solomon, assistant director of policy and research at Barnardo's, said the UK's "controlled disclosure" approach was the right way to tackle the situation but warned the scheme must be closely monitored.
"We cautiously welcome it," he said. "It has a role to play in protecting children.
"During the pilot there was no evidence of sex offenders going underground or disappearing.
"Now that they (Home Office) are up-scaling this they need to monitor it to see if there are any negative consequences."