An island off the coast of Washington State has become home to some of the most dangerous paedophiles and sex offenders in the US.

McNeil Island is part of the upscale collection of mansions and vacation homes on Puget Sound, along America's northwestern coast.

But this windswept part of the inlet has earned the nickname 'Paedophile Island' because it houses one of the country's 20 Special Commitment Centres, where 236 sex offenders live.

This high-security prison was for a short time in the 1960s the jail where infamous cult killer Charles Manson was incarcerated.

But since 1991 it is where Washington State sends its sex offenders who have served their sentences, but whom prison authorities still deem "sexually violent predators" who present a grave risk to the public.

Inmates are sent for treatment here until therapists judge they no longer present a risk, but is it notoriously difficult to secure release from these Special Commitment Centres, with many prisoners languishing here for a decade or more.

The Supreme Court ruled that these facilities were legal in 1997, and last year its judges defied libertarian campaigners, who say these prisoners should be released after their sentences have been served, by refusing to revisit this issue last year.

One inmate, only referred to as Justin, spoke to US current affairs website Vice News about his time on McNeil island. He spent five years in prison and then spent more than a decade at the Special Commitment Centre before convincing authorities he could be released.

Justin said like many sex offenders he was abused as a child. The website did not disclose Justin's crime.

Manage risk

He said: "I will tell you that it took forever for me to forgive myself for what I have done.

"I don't have any urges towards children, I don't have any struggles about urges towards children. I honestly am baffled because it's like I just stop thinking about it."

But Justin's lawyer Rachel Forde said the centres were a dishonest way to treat offenders.

Forde said: "If our society gets together and says: 'We want life sentences for all sex offenders', then we should just be honest about that and say that and change our laws."

But the clinical director at McNeil Island Elena Lopez said the main aim of these centres was to "manage risk" these prisoners pose.

She said: "The purpose of our treatment programme is to manage their risk. It's not to eradicate or eliminate or get rid of, because most of our residents may always have a proclivity for deviancy in some way whether that's for children or non-consensual sex or other."