The number of registered sex offenders in the U.K is not as high as 850,000. This was a top-end estimate of people who pose a risk to children.
An Instagram post states that there are 850,000 registered child sex offenders in the U.K. The charity Stop IT Now highlights that "anyone cautioned or convicted for a sexual offense is put on the sex offenders register( SOR)."
On May 25, 2021, the National Crime Agency (NCA) released a report which estimated that "between 550,000 and 850,000 people pose a sexual risk to children." These estimates were based on individuals who had accessed the dark web to obtain images of child abuse and from the U.K.'s Registered Sex Offenders (RSO) list. In 2021, the NCA applied a new methodology to enhance their understanding of this threat.
Parents Protect, a website that provides information and advice on sexual abuse and exploitation, noted that "no public sex offenders register is available in the U.K." However, if you have concerns about a specific adult, via Sarah's Law, you have the right to ask if they are a sex offender or if they pose a risk to children.
Using a Freedom of Information request, the Telegraph obtained a report from the Ministry of Justice which found that there were 95,844 RSO in England and Wales in March 2020, while the Scottish Sun reported 4,358 RSO in Scotland by the end of March 2020, Full Fact reports.
The Office of National Statistics (ONS) published the Crime Survey for England and Wales (CSEW) findings, which noted that 773,000 adults aged 16 to 74 years were victims of sexual assault by the end of March 2020. Helen Ross from the ONS Centre for Crime and Justice noted a decrease in the prevalence of sexual assault, where only 162,936 sexual offenses were recorded by the end of March 2020 compared to 2018-19.
The duration of the sex offender registration "depends on the offense you have committed and the sentence you have been given," states Stop It Now.
The number of RSOs has been overestimated in this post. Furthermore, the NCA has deployed a new methodology that could have produced differences in numbers. The RSO numbers keep changing according to the duration the individual is sentenced.