One in eight of today's male prison population is in jail for sexual offences - an undreamt of statistic a decade ago. Many people feel it's the best place for them, and would further support throwing away the key.

However, the key isn't thrown away, and the doors that clanged shut do eventually open: "Everyone that goes in, comes out," says psychologist Dr Ian O'Donnell, director of the Irish Penal Reform Trust. "Of the 68 sex offenders due for release this year, many have served their sentences without ever being challenged to confront their offending behaviour. This is a whole new prison population."

At present there are 280 convicted sex offenders in the Republic's prisons, a figure that will rise, at least in the short-term, as pending cases come to court, and because of lengthy sentences. Up to 100 offenders are in prison in the Curragh - isolated and segregated in an unhealthy vacuum.

To "ghettoise" prisoners in order to offer a challenging, therapeutic environment is one thing, says O'Donnell, but to herd them together and offer nothing else is quite another: "There is a danger that these people will be feeding each other's fantasies, reinforcing each other's denial and victim blame," he says. Sex offenders, unlike other categories, are not eligible for early release, temporary release or sentence review. In essence, they sit out their sentence probably untouched by therapy and then emerge with perhaps the same mind-set as that which they entered. "This discrimination means that there is no opportunity for them to be progressively reintegrated, under supervision, into the community," says O'Donnell.

This could arguably leave the State exposed should a case be taken on the grounds of failure to protect the community against known risk.

"The Treatment of Sex Offenders" is the theme of an Irish Penal Reform Trust conference this weekend. There will be speakers from the Department of Justice, the Probation and Welfare Service, the Granada Institute, as well as a look at treatment practices in other countries. The conference message is simple: treatment for sexual offenders in prison can work and is the beginning of a process that must continue in the community.

Speakers will argue that segregating such prisoners without therapy is unhelpful, that post-prison supervision and support is necessary and that a register of paedophiles won't provide a simple solution to a complex problem. At present, in the Republic, the only inhouse treatment available is a 10-place course each year in Dublin's Arbour Hill prison. Incredibly, there are vacancies but there is no incentive for prisoners to seek treatment and few do so.

This situation has been allowed to continue partly because of public pessimism regarding the effectiveness of such programmes, and also out of the belief that forcing someone into treatment would veto its success. But experience in other countries suggests that treatment programmes can work, even when a prisoner is mandated to attend, rather than choosing to do so.

The Department of Justice didn't wish to discuss the Arbour Hill course before the conference, but another conference speaker, Dr James Kelly, explained the goals that such courses generally have. With a doctorate in psychiatric social work, he is a former director of mental health services at the Hawaii Department of Public Safety and Corrections. Prison therapy for sex offenders is, he says, usually offered in a group setting by a specially trained facilitator. There are four typical goals:

The first is to have participants gain insight into the chain of events which trigger their abusive thoughts and behaviour, and their coping mechanisms in response.

The second is to help the offender develop empathy with the victim.

The third is to correct the kind of distorted thinking in which an offender can give himself a behaviour rationale: "They say things like `she was asking for it', or `I was just giving him some sex education'," says Kelly. "It's part of the denial and minimisation that can go on."

Fourth, the offender's response to objective stimuli is tested to allow the therapist gauge what progress has been made.

In Canada and Hawaii, such programmes are the first step in a pre-release programme. The next step could be highly monitored periods of temporary release. Therapy continues in the community after the prisoner is finally released, and will probably be much more challenging as participants are surrounded by stimuli which triggered the offending behaviour in the past. There may be an agreed waiver of the confidentiality in which therapy is normally shrouded, allowing relevant others to know how the offender is faring. The programme will involve much inter-agency co-operation linking families, victims, probation or parole services (which have special offender units), community services, therapists and offenders in ongoing evaluation.

"There is a constant awareness of the cycle of events, so that if, for example, someone who has sexually abused children gets a job, and you hear it's delivering milk at the local school, that will send the red flags up," says Kelly.

Such community work can last for two to four years after release, but the outcomes are positive. "Most of the studies indicate a 7080 per cent success rate, with recidivism occurring in a minority of cases only," he says. He agrees that such long-term, flexible programmes are not a cheap option. "However, when you consider the cost of keeping someone in prison, and the real cost of sexual abuse, it is worth it. And remember, while the offender might be the subject of the therapy, the real clients are the children and the safety of the community."

The Penal Reform Trust believes such an approach could work here. In a recent submission, the trust called for the establishment of a parole board to replace the current Sentence Review Group. Early release could become conditional on participation in in-house treatment.

"All prisoners, including sex offenders who may receive longish sentences, should, when they first go into prison, be the subject of a risk assessment plan," says O'Donnell. For sex offenders, this would include participation in treatment in prison, and hold out the prospect of structured and supervised early release and/or temporary release, depending on progress. Treatment would continue in the community as part of a phased programme of release, involving close collaboration between treatment centres, prison managers and the probation and welfare services.

"Already the probation and welfare service have a role with sex offenders whose crimes do not merit prison. They want to do more and they can do more," says O'Donnell. "Their role could include ongoing supervision as part of a lapse prevention programme."

Next Saturday's conference, chaired by Tom O'Malley, Faculty of Law, NUI Galway, is part of a series organised by the Irish Penal Reform Trust to offer a reflective look at aspects of the prison system. There is, says

O'Donnell, an understandable public anxiety about sex crimes, which fuels the political drive towards more and bigger prisons.

But to keep each sex offender in prison currently costs the community £900 a week - money down the drain if the offender walks out without receiving any treatment while inside and then re-offends on release: "People who have done great harm are serving their sentences and being released with very little done for them in prison," he says. "We have literally a captive audience so let's work them hard while they're in there. I think to aim at taking people back into the community in a state that they are not posing a risk to the rest of us is a fairly modest ambition."

The Treatment of Sex Offenders conference takes place next Saturday, 9 a.m.1.30 p.m. at the Bank of Ireland Arts Centre, Foster Place, Dublin 2. Fee: members £10, non-members £15.