In 2026, the Offender Database recorded that Adam O’Sullivan, 34, who has legally changed his name to Mason Johnson, is residing in a caravan in Great Dunmow, Essex. The individual, formerly of Crawley, West Sussex, and Weybridge, Surrey, is a convicted child sex offender who has sought to hide his history of predatory behaviour through a change of identity. It was reported that O’Sullivan was originally unmasked in 2019 during a covert operation targeting online paedophile networks.
The investigation established the deep-rooted nature of O’Sullivan’s sexual interest in young girls. Sussex Police reported that in 2019, the defendant was caught sending nude images of himself and explicit messages to a 14-year-old girl, who was actually an undercover police officer. The prosecution reported that a forensic audit of his devices revealed he was an active member of several networking groups where users shared “vile” and “shameful” material, including videos and images of children being raped and abused.
Judicial Findings and Investigative Detail
The court reported that O’Sullivan pleaded guilty to attempting to incite a child to engage in sexual activity and three counts of making indecent images. Lewes Crown Court heard how the defendant’s participation in online paedophile groups demonstrated a “depraved” commitment to the exploitation of minors. The investigation established that since his initial conviction, O’Sullivan has demonstrated a persistent failure to comply with the law, breaching his Sexual Offences Prevention Order (SOPO) on multiple occasions.
Essex Police and Sussex Police noted that the defendant’s relocation to a caravan in Great Dunmow and his name change to Mason Johnson represent a deliberate attempt to “start over” and bypass community awareness. For his actions in the South East, he remains under the strictest level of monitoring. The judge noted that his repeated breaches of court orders confirm he remains a clear and present danger to young girls, necessitating constant supervision by the Public Protection Unit.
Status and Statutory Requirements
For the crimes reported in England, the status of Adam O’Sullivan (Mason Johnson) is as follows:
- Current Status: Living in the community under high-level supervision (2026).
- Identity Change: Legally changed name from Adam O’Sullivan to Mason Johnson.
- Sex Offenders Register: Notification requirements are active for life.
- SOPO/SHPO Status: Active, with specific restrictions on internet use and contact with minors.
- Judicial Oversight: Subject to ongoing monitoring by Essex Police following convictions in Sussex.
- Criminal Record: Inciting a child to engage in sexual activity; Making indecent images (3 counts); Breach of SOPO (multiple).
- Origin: Crawley, West Sussex; Weybridge, Surrey (Current: Great Dunmow, Essex).
Monitoring and Public Protection
The individual is managed under Multi-Agency Public Protection Arrangements (MAPPA) by the police and the National Probation Service in Essex. Due to the nature of his conduct in Crawley and his recent move to Great Dunmow, which involved a change of name to evade detection, his management is subject to the highest level of scrutiny. Authorities state that his life-long inclusion on the Sex Offenders Register ensures that his new identity as Mason Johnson is fully recorded and linked to his “warped” criminal past.
As a member of the Sex Offenders Register for life, the defendant must notify the police of any change in his name, address, or travel plans. Authorities state that his history of seeking out “vile” and “disgusting” material and his attempts to hide his identity in Essex necessitate permanent vigilance. Any future attempt to contact children, use unmonitored devices, or breach his residency conditions in Great Dunmow, Chelmsford, or elsewhere will result in immediate arrest and a return to the court system for further incarceration.
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