A deputy says he will lobby the States to change the law so convicted paedophiles and other criminals are not allowed into the island.
Deputy Lester Queripel asked the Home Department whether it could amend legislation relating to the Common Travel Area.
He did so after Anthony Luckwill, an Irish National with a dual UK passport, came to Guernsey and tried to lure a 14-year-old boy back to his hotel room.
Luckwill recently completed a five month prison sentence for inciting a child to commit an act of gross indecency.
He was released on Friday 16th November and could have chosen to stay in Guernsey but decided to leave.
Deputy Queripel does not want a repeat of the situation and said the law, as it stood, allowed convicted paedophiles and rapists to visit Guernsey from anywhere within the UK, the Republic of Ireland and the Isle of Man.
"This is an extremely dangerous and damaging law, because it places our fellow islanders, and our children, in an incredibly vulnerable position."
He said the fact that Luckwill - who has previous convictions - was allowed to enter the island in the first place and decide whether or not he could stay on release, was deplorable.
However, the Home Department has warned that changing the law would mean that islanders without a passport would not be able to travel to the UK.
The minister has also stressed that the island has good border controls and Luckwill was identified soon after arriving.