Ten children are among more than 50 people handed letters by police warning them they are suspected of being sex offenders.
Hampshire police are using the leaflets to tell suspects who they don't have enough evidence to charge that are monitoring their behaviour.
Of the 54 people who have sent the notices in the last two years, 10 are aged under 18, while two are women, according to figures supplied by the force.
Nine recipients later went on to be charged with a sexual offence.
The police force said the notices were used in cases where officers did not have enough evidence to charge a person with an offence but were still concerned about their sexual behaviour.
A total of 52 were given to men and two to women, with 34 handed to people aged 25 and under – and 10 of those were under 18.
The police added those being handed the notices would also be educated about consent and the law surrounding child sex exploitation crimes.
The letter includes warnings to recipients that communicating with anyone aged under 18 about sex could be a criminal offence, sex with anyone aged under 16 is illegal and that people under the influence of drink or drugs cannot consent to sex.
The scheme has been criticised by critics who say it could potentially persecute the innocent.
The warning notice could show up in an enhanced DBS check - the type of background search carried out by employers for roles working with children.
A Hampshire police spokeswoman said: ‘We have introduced a new process for changing potential perpetrator behaviour in CSE cases which do not result in a person being charged.
‘Working with a leading criminologist Dr Graham Hill and the Lucy Faithfull Foundation, a disruption notice known as C5 Notice has been developed.
‘The notice makes clear the law around sexual offending and what types of behaviour and acts are unacceptable.
‘The notice will only be served on perpetrators who have been released with no further action following a thorough police investigation or where intelligence exists that cannot be developed and service of the notice would not increase the risk to a victim.
"Since the process was introduced 54 notices have been issued. Nine people issued with the notice went on to be charged with a sexual offence."
However, one defence lawyer claimed the notice was 'criminalisation by default' and didn't use the 'proper mechanisms set out by parliament' to protect peoples rights.
Aine Kervick, a criminal defence lawyer at Kingsley Napley, said the notices risked damaging people's rights and reputations.
She said: ‘The employer of the future is not going to look behind it.
‘They're just going to see that you've received a warning notice for child sexual exploitation and have serious concerns about your suitability.
‘This is criminalisation by default and doesn't use the proper mechanisms that have been set out by parliament to ensure that peoples due process rights are protected.’
One example of a notice being handed out was of a woman who was reported to police after 15 and 16-year-old boys were seen in her flat.
One Hampshire police sergeant, Antony Waghorn said officers were able to educate the recipient on the law and have a look around the person's home.
The woman has not come to police attention since being issued with the notice.
Labour MP Sarah Champion, co-chair of the All Party Parliamentary Group on Preventing Sexual Violence, said she was in favour of the initiative.
She said: ‘What I'm hoping is, with Hampshire Police issuing these notices, it stops people in their tracks.
‘That it makes them realise what they're doing or what they're potentially thinking about is a crime.
‘That's the best way to protect children.’
However, Police and Crime Commissioner Vera Baird, the national lead for child sexual abuse cases and a former barrister, said she was worried the scheme 'won't protect a soul'.
She added: ‘I don't know of anything else like this at all. There's nothing like a prospect of a conviction with this.
‘Cuts in the budget and a vastly increased demand on policing are likely to have played a part in its use.’
The Home Office says it has made £2.6m of funding available to support the development of preventative schemes to complement existing statutory approaches.