The numbers of Irish sex offenders failing to report to the Irish police - breaching their own notification requirements - doubled last year.
Currently native and foreign born sex offenders residing in Ireland are obliged to inform the Irish police of their name, date of birth, home address and any changes to their residency under the Sex Offenders Act 2001.
But figures show that there were 16 breaches of notification requirements in 2008, and the figure jumped to 50 last year.
There were ten prosecutions for breaches in 2008 and, reflecting the number of breaches, this increased to fifteen in 2009, with a shocking twenty one in the first half of 2010.
In recent years the breaches have resulted in prosecutions, including three convictions in 2008, nine in 2009 and fifteen in the first six months of 2010.
Official Irish police figures show there were more than 1,100 registered sex offenders for each of the years 2008 to 2011. This means that one in every twenty offenders - or five percent - breached their conditions in 2010.
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Responding to the latest figures Fine Gael's Denis Naughten said the new Sexual Offences Bill would give Irish police the legal powers to inform people where a sex offender posed a risk.
'It's clear the registration process in itself is not working,' Naughten told the Evening Herald.
'That clearly makes the argument we need to introduce legislation that will give parents and community organisations information regarding individuals in certain circumstances.'
'Are gardai identifying all of them?' Naughten warned. 'Are people slipping through the net?'